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Jung Y, Kwon K, Lee J, Ko SH. Untethered soft actuators for soft standalone robotics. Nat Commun 2024; 15:3510. [PMID: 38664373 DOI: 10.1038/s41467-024-47639-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Soft actuators produce the mechanical force needed for the functional movements of soft robots, but they suffer from critical drawbacks since previously reported soft actuators often rely on electrical wires or pneumatic tubes for the power supply, which would limit the potential usage of soft robots in various practical applications. In this article, we review the new types of untethered soft actuators that represent breakthroughs and discuss the future perspective of soft actuators. We discuss the functional materials and innovative strategies that gave rise to untethered soft actuators and deliver our perspective on challenges and opportunities for future-generation soft actuators.
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Affiliation(s)
- Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Kangkyu Kwon
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jinwoo Lee
- Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul, 04620, South Korea.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Engineering Research / Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea.
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2
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Yong SH, Kim SM, Kong GW, Ko SH, Lee EH, Oh Y, Yong SH. ASCL1-mediated direct reprogramming: converting ventral midbrain astrocytes into dopaminergic neurons for Parkinson's disease therapy. BMB Rep 2024:6123. [PMID: 38649147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
Parkinson's disease (PD), characterized by dopaminergic neuron degeneration in the substantia nigra, is caused by various genetic and environmental factors. Current treatment methods are medication and surgery; however, a primary therapy has not yet been proposed. In this study, we aimed to develop a new treatment for PD that induces direct reprogramming of dopaminergic neurons (iDAN). Achaete-scute family bHLH transcription factor 1 (ASCL1) is a primary factor that initiates and regulates central nervous system development and induces neurogenesis. In addition, it interacts with BRN2 and MYT1L, which are crucial transcription factors for the direct conversion of fibroblasts into neurons. Overexpression of ASCL1 along with the transcription factors NURR1 and LMX1A can directly reprogram iDANs. Using a retrovirus, GFP-tagged ASCL1 was overexpressed in astrocytes. One week of culture in iDAN convertsion medium reprogrammed the astrocytes into iDANs. After 7 days of differentiation, TH+/TUJ1+ cells emerged. After 2 weeks, the number of mature TH+/TUJ1+ dopaminergic neurons increased. Only ventral midbrain (VM) astrocytes exhibited these results, not cortical astrocytes. Thus, VM astrocytes can undergo direct iDAN reprogramming with ASCL1 alone, in the absence of transcription factors that stimulate dopaminergic neuron development.
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Affiliation(s)
- Sang Hui Yong
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
| | - Sang-Mi Kim
- Hanyang Biomedical Research Institute, Hanyang University, Seoul 04763; Center for Embryo and Stem Cell Research, CHA Advanced Research Institute, CHA University, Seongnam 13488, Korea
| | - Gyeong Woon Kong
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
| | - Seung Hwan Ko
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
| | - Eun-Hye Lee
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Yohan Oh
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763; Hanyang Biomedical Research Institute, Hanyang University, Seoul 04763; Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul 04763; Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul 04763; Hanyang Institute of Advanced BioConvergence, Hanyang University, Seoul 04763, Korea
| | - Sang Hui Yong
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763; Hanyang Biomedical Research Institute, Hanyang University, Seoul 04763, Korea
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3
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Choi SH, Kim JH, Ahn J, Kim T, Jung Y, Won D, Bang J, Pyun KR, Jeong S, Kim H, Kim YG, Ko SH. Phase patterning of liquid crystal elastomers by laser-induced dynamic crosslinking. Nat Mater 2024:10.1038/s41563-024-01845-9. [PMID: 38532072 DOI: 10.1038/s41563-024-01845-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 02/21/2024] [Indexed: 03/28/2024]
Abstract
Liquid crystal elastomers hold promise in various fields due to their reversible transition of mechanical and optical properties across distinct phases. However, the lack of local phase patterning techniques and irreversible phase programming has hindered their broad implementation. Here we introduce laser-induced dynamic crosslinking, which leverages the precision and control offered by laser technology to achieve high-resolution multilevel patterning and transmittance modulation. Incorporation of allyl sulfide groups enables adaptive liquid crystal elastomers that can be reconfigured into desired phases or complex patterns. Laser-induced dynamic crosslinking is compatible with existing processing methods and allows the generation of thermo- and strain-responsive patterns that include isotropic, polydomain and monodomain phases within a single liquid crystal elastomer film. We show temporary information encryption at body temperature, expanding the functionality of liquid crystal elastomer devices in wearable applications.
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Affiliation(s)
- Seok Hwan Choi
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Ju Hee Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Jiyong Ahn
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Taegyeom Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Yeongju Jung
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Daeyeon Won
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Junhyuk Bang
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Kyung Rok Pyun
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Seongmin Jeong
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Hyunsu Kim
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea
| | - Young Gyu Kim
- Department of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul, Republic of Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul, Republic of Korea.
- Institute of Engineering Research / Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Seoul, Republic of Korea.
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, Korea.
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Kim M, Hong S, Park JJ, Jung Y, Choi SH, Cho C, Ha I, Won P, Majidi C, Ko SH. A Gradient Stiffness-Programmed Circuit Board by Spatially Controlled Phase-Transition of Supercooled Hydrogel for Stretchable Electronics Integration. Adv Mater 2024:e2313344. [PMID: 38380843 DOI: 10.1002/adma.202313344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/25/2024] [Indexed: 02/22/2024]
Abstract
Due to emerging demands in soft electronics, there is an increasing need for material architectures that support robust interfacing between soft substrates, stretchable electrical interconnects, and embedded rigid microelectronics chips. Though researchers have adopted rigid-island structures to solve the issue, this approach merely shifts stress concentrations from chip-conductor interfaces to rigid-island-soft region interfaces in the substrate. Here, a gradient stiffness-programmed circuit board (GS-PCB) that possesses high stretchability and stability with surface mounted chips is introduced. The board comprises a stiffness-programmed hydrogel substrate and a laser-patterned liquid metal conductor. The hydrogel simultaneously obtains a large stiffness disparity and robust interfaces between rigid-islands and soft regions. These seemingly contradictory conditions are accomplished by adopting a gradient stiffness structure at the interfaces, enabled by combining polymers with different interaction energies and a supercooled sodium acetate solution. By integrating the gel with laser-patterned liquid metal with exceptional properties, GS-PCB exhibits higher electromechanical stability than other rigid-island research. To highlight the practicality of this approach, a finger-sensor device that successfully distinguishes objects by direct physical contact is fabricated, demonstrating its stability under various mechanical disturbances.
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Affiliation(s)
- Minwoo Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Sangwoo Hong
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jung Jae Park
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Seok Hwan Choi
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Chulmin Cho
- Mechatronics Research, Device Solution, Samsung Electronics, 1, Samsungjeonja-ro, Hwaseong-si, Gyeonggi-do, 18848, South Korea
| | - Inho Ha
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Phillip Won
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Carmel Majidi
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- Institute of Engineering Research/Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- Interdisciplinary Program in Bioengineering, Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
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5
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Pyun KR, Kwon K, Yoo MJ, Kim KK, Gong D, Yeo WH, Han S, Ko SH. Machine-learned wearable sensors for real-time hand-motion recognition: toward practical applications. Natl Sci Rev 2024; 11:nwad298. [PMID: 38213520 PMCID: PMC10776364 DOI: 10.1093/nsr/nwad298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/23/2023] [Accepted: 11/01/2023] [Indexed: 01/13/2024] Open
Abstract
Soft electromechanical sensors have led to a new paradigm of electronic devices for novel motion-based wearable applications in our daily lives. However, the vast amount of random and unidentified signals generated by complex body motions has hindered the precise recognition and practical application of this technology. Recent advancements in artificial-intelligence technology have enabled significant strides in extracting features from massive and intricate data sets, thereby presenting a breakthrough in utilizing wearable sensors for practical applications. Beyond traditional machine-learning techniques for classifying simple gestures, advanced machine-learning algorithms have been developed to handle more complex and nuanced motion-based tasks with restricted training data sets. Machine-learning techniques have improved the ability to perceive, and thus machine-learned wearable soft sensors have enabled accurate and rapid human-gesture recognition, providing real-time feedback to users. This forms a crucial component of future wearable electronics, contributing to a robust human-machine interface. In this review, we provide a comprehensive summary covering materials, structures and machine-learning algorithms for hand-gesture recognition and possible practical applications through machine-learned wearable electromechanical sensors.
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Affiliation(s)
- Kyung Rok Pyun
- Department of Mechanical Engineering, Seoul National University, Seoul08826, South Korea
| | - Kangkyu Kwon
- Department of Mechanical Engineering, Seoul National University, Seoul08826, South Korea
- IEN Center for Human-Centric Interfaces and Engineering, Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA30332, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA30332, USA
| | - Myung Jin Yoo
- Department of Mechanical Engineering, Seoul National University, Seoul08826, South Korea
| | - Kyun Kyu Kim
- Department of Chemical Engineering, Stanford University, Stanford, CA94305, USA
| | - Dohyeon Gong
- Department of Mechanical Engineering, Ajou University, Suwon-si16499, South Korea
| | - Woon-Hong Yeo
- IEN Center for Human-Centric Interfaces and Engineering, Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA30332, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA30332, USA
| | - Seungyong Han
- Department of Mechanical Engineering, Ajou University, Suwon-si16499, South Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul08826, South Korea
- Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Seoul08826, South Korea
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Jung Y, Kim M, Jeong S, Hong S, Ko SH. Strain-Insensitive Outdoor Wearable Electronics by Thermally Robust Nanofibrous Radiative Cooler. ACS Nano 2024; 18:2312-2324. [PMID: 38190550 DOI: 10.1021/acsnano.3c10241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Stable outdoor wearable electronics are gaining attention due to challenges in sustaining consistent device performance outdoors, where sunlight exposure and user movement can disrupt operations. Currently, researchers have focused on integrating radiative coolers into wearable devices for outdoor thermal management. However, these approaches often rely on heat-vulnerable thermoplastic polymers for radiative coolers and strain-susceptible conductors that are unsuitable for wearable electronics. Here, we introduce mechanically, electrically, and thermally stable wearable electronics even when they are stretched under sunlight to address these challenges. This achievement is realized by integrating a polydimethylsiloxane nanofibrous cooler and liquid metal conductors for a fully stable wearable device. The thermally robust architecture of nanofibers, based on their inherent properties as thermoset polymers, exhibits excellent cooling performance through high solar reflection and thermal emission. Additionally, laser-patterned conductors possess ideal properties for wearable electronics, including strain-insensitivity, nonsmearing behavior, and negligible contact resistance. As proof, we developed wearable electronics integrated with thermally and electromechanically stable components that accurately detect physiological signals in harsh environments, including light exposure, while stretched up to 30%. This work highlights the potential for the development of everyday wearable electronics capable of reliable operation under challenging external conditions, including user-activity-induced stress and sunlight exposure.
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Affiliation(s)
- Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Minwoo Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Seongmin Jeong
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Sangwoo Hong
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
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Jung S, Ko SH, Ahn N, Lee J, Park CH, Hwang J. Role of UPF1-LIN28A interaction during early differentiation of pluripotent stem cells. Nat Commun 2024; 15:158. [PMID: 38167913 PMCID: PMC10762078 DOI: 10.1038/s41467-023-44600-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 12/21/2023] [Indexed: 01/05/2024] Open
Abstract
UPF1 and LIN28A are RNA-binding proteins involved in post-transcriptional regulation and stem cell differentiation. Most studies on UPF1 and LIN28A have focused on the molecular mechanisms of differentiated cells and stem cell differentiation, respectively. We reveal that LIN28A directly interacts with UPF1 before UPF1-UPF2 complexing, thereby reducing UPF1 phosphorylation and inhibiting nonsense-mediated mRNA decay (NMD). We identify the interacting domains of UPF1 and LIN28A; moreover, we develop a peptide that impairs UPF1-LIN28A interaction and augments NMD efficiency. Transcriptome analysis of human pluripotent stem cells (hPSCs) confirms that the levels of NMD targets are significantly regulated by both UPF1 and LIN28A. Inhibiting the UPF1-LIN28A interaction using a CPP-conjugated peptide promotes spontaneous differentiation by repressing the pluripotency of hPSCs during proliferation. Furthermore, the UPF1-LIN28A interaction specifically regulates transcripts involved in ectodermal differentiation. Our study reveals that transcriptome regulation via the UPF1-LIN28A interaction in hPSCs determines cell fate.
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Affiliation(s)
- Seungwon Jung
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea
| | - Seung Hwan Ko
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea
| | - Narae Ahn
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea
| | - Jinsam Lee
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea
| | - Chang-Hwan Park
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea.
| | - Jungwook Hwang
- Graduate School of Biomedical Science & Engineering, Hanyang University, Seoul, Korea.
- Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul, Korea.
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Jung Y, Jeong S, Ahn J, Lee J, Ko SH. High Efficiency Breathable Thermoelectric Skin Using Multimode Radiative Cooling/Solar Heating Assisted Large Thermal Gradient. Small 2024; 20:e2304338. [PMID: 37649174 DOI: 10.1002/smll.202304338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/27/2023] [Indexed: 09/01/2023]
Abstract
This study proposes a Janus structure-based stretchable and breathable thermoelectric skin with radiative cooling (RC) and solar heating (SH) functionalities for sustainable energy harvesting. The challenge of the wearable thermoelectric generator arises from the small temperature difference. Thus, this dual-sided structure maximizes the thermal gradient between the body and the surrounding environment, unlike the previous works that rather concentrate on the efficiency of the thermoelectric generator itself. The Janus structure allows the device to switch to the other mode, optimizing electricity generation from a given weather condition. For these functionalities, for the first time, boron nitride-polydimethylsiloxane (BP) and graphene nanoplatelet-polydimethylsiloxane (GP) nanofiber (NF) are developed as substrates. The BP NF generates the RC capability of ΔTcooling = 4 °C, and the high solar absorbance of the GP NF enables it to be photothermally heated. The flip-overable thermoelectric skin (FoTES) achieves a maximum power output (Pmax ) of 5.73 µW cm-2 in RC mode, surpassing SH mode by 5.55 µW cm-2 in the morning. In the afternoon, it generates a Pmax of 18.59 µW cm-2 in SH mode, outperforming RC mode by 15.56 µW cm-2 . This work contributes to the advancement of wearable electronics, offering a sustainable power source in a wearable form.
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Affiliation(s)
- Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Seongmin Jeong
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jiyong Ahn
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jinwoo Lee
- Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul, 04620, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
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9
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Min J, Jung Y, Ahn J, Lee JG, Lee J, Ko SH. Recent Advances in Biodegradable Green Electronic Materials and Sensor Applications. Adv Mater 2023; 35:e2211273. [PMID: 36934454 DOI: 10.1002/adma.202211273] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/16/2023] [Indexed: 06/18/2023]
Abstract
As environmental issues have become the dominant agenda worldwide, the necessity for more environmentally friendly electronics has recently emerged. Accordingly, biodegradable or nature-derived materials for green electronics have attracted increased interest. Initially, metal-green hybrid electronics are extensively studied. Although these materials are partially biodegradable, they have high utility owing to their metallic components. Subsequently, carbon-framed materials (such as graphite, cylindrical carbon nanomaterials, graphene, graphene oxide, laser-induced graphene) have been investigated. This has led to the adoption of various strategies for carbon-based materials, such as blending them with biodegradable materials. Moreover, various conductive polymers have been developed and researchers have studied their potential use in green electronics. Researchers have attempted to fabricate conductive polymer composites with high biodegradability by shortening the polymer chains. Furthermore, various physical, chemical, and biological sensors that are essential to modern society have been studied using biodegradable compounds. These recent advances in green electronics have paved the way toward their application in real life, providing a brighter future for society.
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Affiliation(s)
- JinKi Min
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jiyong Ahn
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jae Gun Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jinwoo Lee
- Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul, 04620, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
- Institute of Engineering Research/Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
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10
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Song S, Hong H, Kim KY, Kim KK, Kim J, Won D, Yun S, Choi J, Ryu YI, Lee K, Park J, Kang J, Bang J, Seo H, Kim YC, Lee D, Lee H, Lee J, Hwang SW, Ko SH, Jeon H, Lee W. Photothermal Lithography for Realizing a Stretchable Multilayer Electronic Circuit Using a Laser. ACS Nano 2023; 17:21443-21454. [PMID: 37857269 DOI: 10.1021/acsnano.3c06207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Photolithography is a well-established fabrication method for realizing multilayer electronic circuits. However, it is challenging to adopt photolithography to fabricate intrinsically stretchable multilayer electronic circuits fully composed of an elastomeric matrix, due to the opacity of thick stretchable nanocomposite conductors. Here, we present photothermal lithography that can pattern elastomeric conductors and via holes using pulsed lasers. The photothermal-patterned stretchable nanocomposite conductor exhibits 3 times higher conductivity (5940 S cm-1) and 5 orders of magnitude lower resistance change (R/R0 = 40) under a 30% strained 5000th cyclic stretch, compared to those of a screen-printed conductor, based on the percolation network formed by spatial heating of the laser. In addition, a 50 μm sized stretchable via holes can be patterned on the passivation without material ablation and electrical degradation of the bottom conductor. By repeatedly patterning the conductor and via holes, highly conductive and durable multilayer circuits can be stacked with layer-by-layer material integration. Finally, a stretchable wireless pressure sensor and passive matrix LED array are demonstrated, thus showing the potential for a stretchable multilayer electronic circuit with durability, high density, and multifunctionality.
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Affiliation(s)
- Sangmin Song
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Hyejun Hong
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyung Yeun Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyun Kyu Kim
- Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
| | - Jaewoo Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Daeyeon Won
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Soyoung Yun
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Joonhwa Choi
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Young-In Ryu
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyungwoo Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Jaeho Park
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Joohyuk Kang
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Junhyuk Bang
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Hyunseon Seo
- School of Medicine, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Yu-Chan Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Daeho Lee
- Department of Mechanical Engineering, Gachon University, Seongnam 13120, Republic of Korea
| | - Haechang Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Jinwoo Lee
- Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, Seoul 04620, Republic of Korea
| | - Suk-Won Hwang
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Hojeong Jeon
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Wonryung Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science & Technology, University of Science & Technology (UST), Seoul 02792, Republic of Korea
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11
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Blankenship BW, Li R, Guo R, Zhao N, Shin J, Yang R, Ko SH, Wu J, Rho Y, Grigoropoulos C. Photothermally Activated Artificial Neuromorphic Synapses. Nano Lett 2023; 23:9020-9025. [PMID: 37724920 DOI: 10.1021/acs.nanolett.3c02681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Biological nervous systems rely on the coordination of billions of neurons with complex, dynamic connectivity to enable the ability to process information and form memories. In turn, artificial intelligence and neuromorphic computing platforms have sought to mimic biological cognition through software-based neural networks and hardware demonstrations utilizing memristive circuitry with fixed dynamics. To incorporate the advantages of tunable dynamic software implementations of neural networks into hardware, we develop a proof-of-concept artificial synapse with adaptable resistivity. This synapse leverages the photothermally induced local phase transition of VO2 thin films by temporally modulated laser pulses. Such a process quickly modifies the conductivity of the film site-selectively by a factor of 500 to "activate" these neurons and store "memory" by applying varying bias voltages to induce self-sustained Joule heating between electrodes after activation with a laser. These synapses are demonstrated to undergo a complete heating and cooling cycle in less than 120 ns.
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Affiliation(s)
- Brian W Blankenship
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Runxuan Li
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Ruihan Guo
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States
| | - Naichen Zhao
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Jaeho Shin
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea
| | - Rundi Yang
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, South Korea
| | - Junqiao Wu
- Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States
| | - Yoonsoo Rho
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
- Physical & Life Sciences and NIF & Photon Sciences, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Costas Grigoropoulos
- Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
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12
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Choi J, Min J, Kim D, Kim J, Kim J, Yoon H, Lee J, Jeong Y, Kim CY, Ko SH. Hierarchical 3D Percolation Network of Ag-Au Core-Shell Nanowire-Hydrogel Composite for Efficient Biohybride Electrodes. ACS Nano 2023; 17:17966-17978. [PMID: 37668160 DOI: 10.1021/acsnano.3c04292] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Metal nanomaterials are highly valued for their enhanced surface area and electrochemical properties, which are crucial for energy devices and bioelectronics. However, their practical applications are often limited by challenges, such as scalability and dimensional constraints. In this study, we developed a synthesis method for highly porous Ag-Au core-shell nanowire foam (AACNF) using a one-pot process based on a simultaneous nanowelding synthesis method. The unique characteristics of AACNF as metal-based electrodes show the lowest density among metal-based electrodes while demonstrating high electrical conductivity (99.33-753.04 S/m) and mechanical stability. The AACNF's excellent mass transport properties enable multiscale hierarchical incorporation with functional materials including polymeric precursors and living cells. The enhanced mechanical stability at the nanowelded junctions allows AACNF-hydrogel composites to exhibit large stretching (∼700%) and 10,000 times higher electrical conductivity than hydrogel-nanowire composites without the junction. Large particles in the 1-10 μm scale, including fibroblast cells and exoelectrogenic microbes, are also successfully incorporated with AACNF. AACNF-based microbial fuel cells show high power density (∼330.1 W/m3) within the optimal density range. AACNF's distinctive ability to form a hierarchical structure with substances in various scales showcases its potential for advanced energy devices and biohybrid electrodes in the future.
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Affiliation(s)
- Joonhwa Choi
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - JinKi Min
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Dohyung Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Jin Kim
- College of Veterinary Medicine, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Jinsol Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Hyeokjun Yoon
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Jinwoo Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Youngin Jeong
- College of Veterinary Medicine, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - C-Yoon Kim
- College of Veterinary Medicine, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
- Institute of Engineering Research, Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826 Korea
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13
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Park H, Park JJ, Bui PD, Yoon H, Grigoropoulos CP, Lee D, Ko SH. Laser-Based Selective Material Processing for Next-Generation Additive Manufacturing. Adv Mater 2023:e2307586. [PMID: 37740699 DOI: 10.1002/adma.202307586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/14/2023] [Indexed: 09/25/2023]
Abstract
The connection between laser-based material processing and additive manufacturing is quite deeply rooted. In fact, the spark that started the field of additive manufacturing is the idea that two intersecting laser beams can selectively solidify a vat of resin. Ever since, laser has been accompanying the field of additive manufacturing, with its repertoire expanded from processing only photopolymer resin to virtually any material, allowing liberating customizability. As a result, additive manufacturing is expected to take an even more prominent role in the global supply chain in years to come. Herein, an overview of laser-based selective material processing is presented from various aspects: the physics of laser-material interactions, the materials currently used in additive manufacturing processes, the system configurations that enable laser-based additive manufacturing, and various functional applications of next-generation additive manufacturing. Additionally, current challenges and prospects of laser-based additive manufacturing are discussed.
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Affiliation(s)
- Huijae Park
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jung Jae Park
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Phuong-Danh Bui
- Laser and Thermal Engineering Lab, Department of Mechanical Engineering, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam, 13120, South Korea
| | - Hyeokjun Yoon
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Costas P Grigoropoulos
- Laser Thermal Lab, Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Daeho Lee
- Laser and Thermal Engineering Lab, Department of Mechanical Engineering, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam, 13120, South Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
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14
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Abstract
Recent advancements in wearable electronics offer seamless integration with the human body for extracting various biophysical and biochemical information for real-time health monitoring, clinical diagnostics, and augmented reality. Enormous efforts have been dedicated to imparting stretchability/flexibility and softness to electronic devices through materials science and structural modifications that enable stable and comfortable integration of these devices with the curvilinear and soft human body. However, the optical properties of these devices are still in the early stages of consideration. By incorporating transparency, visual information from interfacing biological systems can be preserved and utilized for comprehensive clinical diagnosis with image analysis techniques. Additionally, transparency provides optical imperceptibility, alleviating reluctance to wear the device on exposed skin. This review discusses the recent advancement of transparent wearable electronics in a comprehensive way that includes materials, processing, devices, and applications. Materials for transparent wearable electronics are discussed regarding their characteristics, synthesis, and engineering strategies for property enhancements. We also examine bridging techniques for stable integration with the soft human body. Building blocks for wearable electronic systems, including sensors, energy devices, actuators, and displays, are discussed with their mechanisms and performances. Lastly, we summarize the potential applications and conclude with the remaining challenges and prospects.
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Affiliation(s)
- Daeyeon Won
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Junhyuk Bang
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seok Hwan Choi
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Kyung Rok Pyun
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seongmin Jeong
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Youngseok Lee
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seung Hwan Ko
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
- Institute
of Engineering Research/Institute of Advanced Machinery and Design
(SNU-IAMD), Seoul National University, Seoul 08826, South Korea
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15
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Jeong S, Oh J, Kim H, Bae J, Ko SH. Pattern design of a liquid metal-based wearable heater for constant heat generation under biaxial strain. iScience 2023; 26:107008. [PMID: 37332675 PMCID: PMC10275728 DOI: 10.1016/j.isci.2023.107008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/05/2023] [Accepted: 05/26/2023] [Indexed: 06/20/2023] Open
Abstract
As the wearable heater is increasingly popular due to its versatile applications, there is a growing need to improve the tensile stability of the wearable heater. However, maintaining the stability and precise control of heating in resistive heaters for wearable electronics remains challenging due to multiaxial dynamic deformation with human motion. Here, we propose a pattern study for a circuit control system without complex structure or deep learning of the liquid metal (LM)-based wearable heater. The LM direct ink writing (DIW) method was used to fabricate the wearable heaters in various designs. Through the study about the pattern, the significance of input power per unit area for steady average temperature with tension was proven, and the directionality of the pattern was shown to be a factor that makes feedback control difficult due to the difference in resistance change according to strain direction. For this issue, a wearable heater with the same minimal resistance change regardless of the tension direction was developed using Peano curves and sinuous pattern structure. Lastly, by attaching to a human body model, the wearable heater with the circuit control system shows stable heating (52.64°C, with a standard deviation of 0.91°C) in actual motion.
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Affiliation(s)
- Seongmin Jeong
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Jinhyeok Oh
- Bio-Robotics and Control Lab, Department of Mechanical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan 44919, Korea
| | - Hongchan Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Joonbum Bae
- Bio-Robotics and Control Lab, Department of Mechanical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan 44919, Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
- Institute of Engineering Research/Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
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16
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Jung Y, Kim M, Kim T, Ahn J, Lee J, Ko SH. Functional Materials and Innovative Strategies for Wearable Thermal Management Applications. Nanomicro Lett 2023; 15:160. [PMID: 37386321 PMCID: PMC10310690 DOI: 10.1007/s40820-023-01126-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/13/2023] [Indexed: 07/01/2023]
Abstract
Highlights This article systematically reviews the thermal management wearables with a specific emphasis on materials and strategies to regulate the human body temperature. Thermal management wearables are subdivided into the active and passive thermal managing methods. The strength and weakness of each thermal regulatory wearables are discussed in details from the view point of practical usage in real-life. Abstract Thermal management is essential in our body as it affects various bodily functions, ranging from thermal discomfort to serious organ failures, as an example of the worst-case scenario. There have been extensive studies about wearable materials and devices that augment thermoregulatory functionalities in our body, employing diverse materials and systematic approaches to attaining thermal homeostasis. This paper reviews the recent progress of functional materials and devices that contribute to thermoregulatory wearables, particularly emphasizing the strategic methodology to regulate body temperature. There exist several methods to promote personal thermal management in a wearable form. For instance, we can impede heat transfer using a thermally insulating material with extremely low thermal conductivity or directly cool and heat the skin surface. Thus, we classify many studies into two branches, passive and active thermal management modes, which are further subdivided into specific strategies. Apart from discussing the strategies and their mechanisms, we also identify the weaknesses of each strategy and scrutinize its potential direction that studies should follow to make substantial contributions to future thermal regulatory wearable industries.
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Affiliation(s)
- Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Minwoo Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Taegyeom Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jiyong Ahn
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jinwoo Lee
- Department of Mechanical, Robotics, and Energy Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul, 04620, South Korea.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
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17
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Lee M, Kim G, Jung Y, Pyun KR, Lee J, Kim BW, Ko SH. Photonic structures in radiative cooling. Light Sci Appl 2023; 12:134. [PMID: 37264035 DOI: 10.1038/s41377-023-01119-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 02/03/2023] [Accepted: 02/27/2023] [Indexed: 06/03/2023]
Abstract
Radiative cooling is a passive cooling technology without any energy consumption, compared to conventional cooling technologies that require power sources and dump waste heat into the surroundings. For decades, many radiative cooling studies have been introduced but its applications are mostly restricted to nighttime use only. Recently, the emergence of photonic technologies to achieves daytime radiative cooling overcome the performance limitations. For example, broadband and selective emissions in mid-IR and high reflectance in the solar spectral range have already been demonstrated. This review article discusses the fundamentals of thermodynamic heat transfer that motivates radiative cooling. Several photonic structures such as multilayer, periodical, random; derived from nature, and associated design procedures were thoroughly discussed. Photonic integration with new functionality significantly enhances the efficiency of radiative cooling technologies such as colored, transparent, and switchable radiative cooling applications has been developed. The commercial applications such as reducing cooling loads in vehicles, increasing the power generation of solar cells, generating electricity, saving water, and personal thermal regulation are also summarized. Lastly, perspectives on radiative cooling and emerging issues with potential solution strategies are discussed.
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Affiliation(s)
- Minjae Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- Electronic Device Research Team, Hyundai Motor Group, 37, Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do, 16082, South Korea
| | - Gwansik Kim
- E-drive Materials Research Team, Hyundai Motor Group, 37, Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do, 16082, South Korea
| | - Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Kyung Rok Pyun
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jinwoo Lee
- Department of Mechanical Robotics, and Energy Engineering, Dongguk University, 30 pildong-ro 1-gil, Jung-gu, Seoul, 04620, South Korea
| | - Byung-Wook Kim
- E-drive Materials Research Team, Hyundai Motor Group, 37, Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do, 16082, South Korea.
- Department of Civil Engineering and Engineering Mechanics, Columbia University, New York, NY, 10027, USA.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Advanced Machinery and Design (SNU-IAMD)/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
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18
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Kim Y, Lim J, Lim JH, Hwang E, Lee H, Kim M, Ha I, Cho H, Kwon J, Oh J, Ko SH, Pan H, Hong S. Reconfigurable Multilevel Optical PUF by Spatiotemporally Programmed Crystallization of Supersaturated Solution. Adv Mater 2023; 35:e2212294. [PMID: 36940430 DOI: 10.1002/adma.202212294] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/11/2023] [Indexed: 06/02/2023]
Abstract
Physical unclonable functions (PUFs) are emerging as an alternative to information security by providing an advanced level of cryptographic keys with non-replicable characteristics, yet the cryptographic keys of conventional PUFs are not reconfigurable from the ones assigned at the manufacturing stage and the overall authentication process slows down as the number of entities in the dataset or the length of cryptographic key increases. Herein, a supersaturated solution-based PUF (S-PUF) is presented that utilizes stochastic crystallization of a supersaturated sodium acetate solution to allow a time-efficient, hierarchical authentication process together with on-demand rewritability of cryptographic keys. By controlling the orientation and the average grain size of the sodium acetate crystals via a spatiotemporally programmed temperature profile, the S-PUF now includes two global parameters, that is, angle of rotation and divergence of the diffracted beam, in addition to the speckle pattern to produce multilevel cryptographic keys, and these parameters function as prefixes for the classification of each entity for a fast authentication process. At the same time, the reversible phase change of sodium acetate enables repeated reconfiguration of the cryptographic key, which is expected to offer new possibilities for a next-generation, recyclable anti-counterfeiting platform.
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Affiliation(s)
- Youngchan Kim
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Jaemook Lim
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Ji Hwan Lim
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Eunseung Hwang
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Hyunkoo Lee
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Minwoo Kim
- Department of Mechanical Engineering/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Inho Ha
- Department of Mechanical Engineering/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Hyunmin Cho
- Department of Nano Manufacturing Technology, Korea Institute of Machinery & Materials (KIMM), 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon, 34103, South Korea
| | - Jinhyeong Kwon
- Smart Manufacturing System R&D Department, Korea Institute of Industrial Technology (KITECH), 89 Yangdaegiro-gil, Ipjang-myeon, Seobuk-gu, Chungchengnam-do, Cheonan, 31056, South Korea
| | - Junho Oh
- Bio-inspired Energy and Thermal Transport Engineering Research Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Heng Pan
- Multiscale Manufacturing Lab, J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Sukjoon Hong
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 15588, South Korea
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19
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Lee EH, Kim M, Ko SH, Kim CH, Lee M, Park CH. Primary astrocytic mitochondrial transplantation ameliorates ischemic stroke. BMB Rep 2023; 56:90-95. [PMID: 36195567 PMCID: PMC9978364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Indexed: 02/24/2023] Open
Abstract
Mitochondria are important organelles that regulate adenosine triphosphate production, intracellular calcium buffering, cell survival, and apoptosis. They play therapeutic roles in injured cells via transcellular transfer through extracellular vesicles, gap junctions, and tunneling nanotubes. Astrocytes can secrete numerous factors known to promote neuronal survival, synaptic formation, and plasticity. Recent studies have demonstrated that astrocytes can transfer mitochondria to damaged neurons to enhance their viability and recovery. In this study, we observed that treatment with mitochondria isolated from rat primary astrocytes enhanced cell viability and ameliorated hydrogen peroxide-damaged neurons. Interestingly, isolated astrocytic mitochondria increased the number of cells under damaged neuronal conditions, but not under normal conditions, although the mitochondrial transfer efficiency did not differ between the two conditions. This effect was also observed after transplanting astrocytic mitochondria in a rat middle cerebral artery occlusion model. These findings suggest that mitochondria transfer therapy can be used to treat acute ischemic stroke and other diseases. [BMB Reports 2023; 56(2): 90-95].
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Affiliation(s)
- Eun-Hye Lee
- Hanyang Biomedical Research Institute, Seoul 04763, Korea
| | - Minkyung Kim
- Department of Bioengineering, College of Engineering, Seoul 04763, Korea
| | - Seung Hwan Ko
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
| | | | - Minhyung Lee
- Department of Bioengineering, College of Engineering, Seoul 04763, Korea,Corresponding authors. Minhyung Lee, Tel: +82-2-2220-0484; Fax: +82-2-2220-4454; E-mail: ; Chang-Hwan Park, Tel: +82-2-2220-0646; Fax: +82-2-2220-2422; E-mail: chshpark@ hanyang.ac.kr
| | - Chang-Hwan Park
- Hanyang Biomedical Research Institute, Seoul 04763, Korea,Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea,Department of Microbiology, College of Medicine, Hanyang University, Seoul 04763, Korea,Corresponding authors. Minhyung Lee, Tel: +82-2-2220-0484; Fax: +82-2-2220-4454; E-mail: ; Chang-Hwan Park, Tel: +82-2-2220-0646; Fax: +82-2-2220-2422; E-mail: chshpark@ hanyang.ac.kr
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20
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Kim M, Lim H, Ko SH. Liquid Metal Patterning and Unique Properties for Next-Generation Soft Electronics. Adv Sci (Weinh) 2023; 10:e2205795. [PMID: 36642850 PMCID: PMC9951389 DOI: 10.1002/advs.202205795] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/27/2022] [Indexed: 05/28/2023]
Abstract
Room-temperature liquid metal (LM)-based electronics is expected to bring advancements in future soft electronics owing to its conductivity, conformability, stretchability, and biocompatibility. However, various difficulties arise when patterning LM because of its rheological features such as fluidity and surface tension. Numerous attempts are made to overcome these difficulties, resulting in various LM-patterning methods. An appropriate choice of patterning method based on comprehensive understanding is necessary to fully utilize the unique properties. Therefore, the authors aim to provide thorough knowledge about patterning methods and unique properties for LM-based future soft electronics. First, essential considerations for LM-patterning are investigated. Then, LM-patterning methods-serial-patterning, parallel-patterning, intermetallic bond-assisted patterning, and molding/microfluidic injection-are categorized and investigated. Finally, perspectives on LM-based soft electronics with unique properties are provided. They include outstanding features of LM such as conformability, biocompatibility, permeability, restorability, and recyclability. Also, they include perspectives on future LM-based soft electronics in various areas such as radio frequency electronics, soft robots, and heterogeneous catalyst. LM-based soft devices are expected to permeate the daily lives if patterning methods and the aforementioned features are analyzed and utilized.
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Affiliation(s)
- Minwoo Kim
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826South Korea
| | - Hyungjun Lim
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826South Korea
- Department of Mechanical EngineeringPohang University of Science and Technology77 Chungam‐ro, Nam‐guPohang37673South Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826South Korea
- Institute of Advanced Machinery and Design/Institute of Engineering ResearchSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826South Korea
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21
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Truong PL, Yin Y, Lee D, Ko SH. Advancement in COVID-19 detection using nanomaterial-based biosensors. Exploration (Beijing) 2023; 3:20210232. [PMID: 37323622 PMCID: PMC10191025 DOI: 10.1002/exp.20210232] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 05/11/2022] [Indexed: 06/17/2023]
Abstract
Coronavirus disease 2019 (COVID-19) pandemic has exemplified how viral growth and transmission are a significant threat to global biosecurity. The early detection and treatment of viral infections is the top priority to prevent fresh waves and control the pandemic. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been identified through several conventional molecular methodologies that are time-consuming and require high-skill labor, apparatus, and biochemical reagents but have a low detection accuracy. These bottlenecks hamper conventional methods from resolving the COVID-19 emergency. However, interdisciplinary advances in nanomaterials and biotechnology, such as nanomaterials-based biosensors, have opened new avenues for rapid and ultrasensitive detection of pathogens in the field of healthcare. Many updated nanomaterials-based biosensors, namely electrochemical, field-effect transistor, plasmonic, and colorimetric biosensors, employ nucleic acid and antigen-antibody interactions for SARS-CoV-2 detection in a highly efficient, reliable, sensitive, and rapid manner. This systematic review summarizes the mechanisms and characteristics of nanomaterials-based biosensors for SARS-CoV-2 detection. Moreover, continuing challenges and emerging trends in biosensor development are also discussed.
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Affiliation(s)
- Phuoc Loc Truong
- Laser and Thermal Engineering LabDepartment of Mechanical EngineeringGachon UniversitySeongnamKorea
| | - Yiming Yin
- New Materials InstituteDepartment of MechanicalMaterials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingboChina
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National UniversityGwanak‐guSeoulKorea
| | - Daeho Lee
- Laser and Thermal Engineering LabDepartment of Mechanical EngineeringGachon UniversitySeongnamKorea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National UniversityGwanak‐guSeoulKorea
- Institute of Advanced Machinery and Design (SNU‐IAMD)/Institute of Engineering ResearchSeoul National UniversityGwanak‐guSeoulKorea
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22
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Lee EH, Kim M, Ko SH, Kim CH, Lee M, Park CH. Primary astrocytic mitochondrial transplantation ameliorates ischemic stroke. BMB Rep 2023; 56:90-95. [PMID: 36195567 PMCID: PMC9978364 DOI: 10.5483/bmbrep.2022-0108] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/02/2022] [Accepted: 09/14/2022] [Indexed: 08/13/2023] Open
Abstract
Mitochondria are important organelles that regulate adenosine triphosphate production, intracellular calcium buffering, cell survival, and apoptosis. They play therapeutic roles in injured cells via transcellular transfer through extracellular vesicles, gap junctions, and tunneling nanotubes. Astrocytes can secrete numerous factors known to promote neuronal survival, synaptic formation, and plasticity. Recent studies have demonstrated that astrocytes can transfer mitochondria to damaged neurons to enhance their viability and recovery. In this study, we observed that treatment with mitochondria isolated from rat primary astrocytes enhanced cell viability and ameliorated hydrogen peroxide-damaged neurons. Interestingly, isolated astrocytic mitochondria increased the number of cells under damaged neuronal conditions, but not under normal conditions, although the mitochondrial transfer efficiency did not differ between the two conditions. This effect was also observed after transplanting astrocytic mitochondria in a rat middle cerebral artery occlusion model. These findings suggest that mitochondria transfer therapy can be used to treat acute ischemic stroke and other diseases. [BMB Reports 2023; 56(2): 90-95].
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Affiliation(s)
- Eun-Hye Lee
- Hanyang Biomedical Research Institute, Seoul 04763, Korea
| | - Minkyung Kim
- Department of Bioengineering, College of Engineering, Seoul 04763, Korea
| | - Seung Hwan Ko
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
| | | | - Minhyung Lee
- Department of Bioengineering, College of Engineering, Seoul 04763, Korea
| | - Chang-Hwan Park
- Hanyang Biomedical Research Institute, Seoul 04763, Korea
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea
- Department of Microbiology, College of Medicine, Hanyang University, Seoul 04763, Korea
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23
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Won P, Coyle S, Ko SH, Quinn D, Hsia KJ, LeDuc P, Majidi C. Controlling C2C12 Cytotoxicity on Liquid Metal Embedded Elastomer (LMEE). Adv Healthc Mater 2023:e2202430. [PMID: 36706458 DOI: 10.1002/adhm.202202430] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 01/17/2023] [Indexed: 01/28/2023]
Abstract
Liquid metal embedded elastomers (LMEEs) are highly stretchable composites comprised of microscopic droplets of eutectic gallium-indium (EGaIn) liquid metal embedded in a soft rubber matrix. They have a unique combination of mechanical, electrical, and thermal properties that make them attractive for potential applications in flexible electronics, thermal management, wearable computing, and soft robotics. However, the use of LMEEs in direct contact with human tissue or organs requires an understanding of their biocompatibility and cell cytotoxicity. In this study, we investigate the cytotoxicity of C2C12 cells in contact with LMEE composites composed of EGaIn droplets embedded with a polydimethylsiloxane (PDMS) matrix. In particular, we examine the influence of EGaIn volume ratio and shear mixing time during synthesis on cell proliferation and viability. We also examine the special case of electrically-conductive LMEE composites in which a percolating network of EGaIn droplets is created through "mechanical sintering." This study in C2C12 cytotoxicity represents a first step in determining whether LMEE is safe for use in implantable biomedical devices and biohybrid systems. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Phillip Won
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Stephen Coyle
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Seung Hwan Ko
- Mechanical Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - David Quinn
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - K Jimmy Hsia
- Chemical & Biomedical Engineering, Nanyang Technical University, Singapore, 639798, Singapore.,Mechanical & Aerospace Engineering, Nanyang Technical University, Singapore, 639798, Singapore
| | - Philip LeDuc
- Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Carmel Majidi
- Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
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24
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Ko SH, Kang JS, Kim SM, Lee EH, Park CH. Reduced Cytotoxicity by Repetitive mRNA Transfection in Differentiated Neurons. Int J Stem Cells 2022; 16:117-122. [PMID: 36581368 PMCID: PMC9978836 DOI: 10.15283/ijsc22125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/01/2022] [Accepted: 11/07/2022] [Indexed: 12/31/2022] Open
Abstract
Background and Objectives mRNA-based protein expression technology has been used to express functional proteins. We have previously generated dopamine neurons from rat-embryo derived neural precursor cells (NPCs) through repeated transfection of synthetic transcription factor mRNA encoding dopamine-inducible genes. However, NPCs began to die approximately 10 d post-transfection. In this study, we examined a long-term transfection protocol that did not affect cell viability. Methods and Results Experiments were performed in eight groups sorted according to the start date of mRNA transfection. mRNA was transfected into NPCs daily for 21 d and live cell images of each group were recorded. NPCs which were differentiated for more than five days showed sustained gene expression and appreciable viability despite daily mRNA transfection for 21 d. Conclusions Repeated mRNA transfection requires cells with a sufficient differentiation period.
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Affiliation(s)
- Seung Hwan Ko
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, Korea
| | - Jin Sun Kang
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, Korea
| | - Sang-Mi Kim
- Hanyang Biomedical Research Institute, Hanyang University, Seoul, Korea
| | - Eun-Hye Lee
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chang-Hwan Park
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, Korea,Hanyang Biomedical Research Institute, Hanyang University, Seoul, Korea,Department of Microbiology, College of Medicine, Hanyang University, Seoul, Korea,Correspondence to Chang-Hwan Park, Graduate School of Biomedical Science & Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea, Tel: +82-2-2220-0646, Fax: +82-2-2220-2422, E-mail:
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25
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Won P, Valentine CS, Zadan M, Pan C, Vinciguerra M, Patel DK, Ko SH, Walker LM, Majidi C. 3D Printing of Liquid Metal Embedded Elastomers for Soft Thermal and Electrical Materials. ACS Appl Mater Interfaces 2022; 14:55028-55038. [PMID: 36458663 DOI: 10.1021/acsami.2c14815] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Liquid metal embedded elastomers (LMEEs) are composed of a soft polymer matrix embedded with droplets of metal alloys that are liquid at room temperature. These soft matter composites exhibit exceptional combinations of elastic, electrical, and thermal properties that make them uniquely suited for applications in flexible electronics, soft robotics, and thermal management. However, the fabrication of LMEE structures has primarily relied on rudimentary techniques that limit patterning to simple planar geometries. Here, we introduce an approach for direct ink write (DIW) printing of a printable LMEE ink to create three-dimensional shapes with various designs. We use eutectic gallium-indium (EGaIn) as the liquid metal, which reacts with oxygen to form an electrically insulating oxide skin that acts as a surfactant and stabilizes the droplets for 3D printing. To rupture the oxide skin and achieve electrical conductivity, we encase the LMEE in a viscoelastic polymer and apply acoustic shock. For printed composites with a 80% LM volume fraction, this activation method allows for a volumetric electrical conductivity of 5 × 104 S cm-1 (80% LM volume)─significantly higher than what had been previously reported with mechanically sintered EGaIn-silicone composites. Moreover, we demonstrate the ability to print 3D LMEE interfaces that provide enhanced charge transfer for a triboelectric nanogenerator (TENG) and improved thermal conductivity within a thermoelectric device (TED). The 3D printed LMEE can be integrated with a highly soft TED that is wearable and capable of providing cooling/heating to the skin through electrical stimulation.
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Affiliation(s)
- Phillip Won
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Connor S Valentine
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Mason Zadan
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Chengfeng Pan
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR999077, China
| | - Michael Vinciguerra
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Dinesh K Patel
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul08826, Republic of Korea
| | - Lynn M Walker
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
| | - Carmel Majidi
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania15213, United States
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26
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Abstract
The metaverse may change the way we live and interact with one another, and its potential applications range from entertainment to health care. Extended reality is the main technology to realize the highly realistic, interactive and immersive metaverse experience, and wearable electronic devices and materials are at its core.
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Affiliation(s)
- Kyung Rok Pyun
- Mechanical Engineering Department, Seoul National University, Gwanak-gu, Seoul South Korea
| | - John A. Rogers
- Querrey Simpson Institute for Bioelectronics, Northwestern University, Evanston, IL USA
| | - Seung Hwan Ko
- Mechanical Engineering Department, Seoul National University, Gwanak-gu, Seoul South Korea
- Institute of Engineering Research, Seoul National University, Gwanak-gu, Seoul South Korea
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27
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Cho C, Shin W, Kim M, Bang J, Won P, Hong S, Ko SH. Monolithically Programmed Stretchable Conductor by Laser-Induced Entanglement of Liquid Metal and Metallic Nanowire Backbone. Small 2022; 18:e2202841. [PMID: 35901286 DOI: 10.1002/smll.202202841] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/19/2022] [Indexed: 06/15/2023]
Abstract
Owing to its low mechanical compliance, liquid metal is intrinsically suitable for stretchable electronics and future wearable devices. However, its invariable strain-resistance behavior according to the strain-induced geometrical deformation and the difficulty of circuit patterning limit the extensive use of liquid metal, especially for strain-insensitive wiring purposes. To overcome these limitations, herein, novel liquid-metal-based electrodes of fragmented eutectic gallium-indium alloy (EGaIn) and Ag nanowire (NW) backbone of which their entanglement is controlled by the laser-induced photothermal reaction to enable immediate and direct patterning of the stretchable electrode with spatially programmed strain-resistance characteristics are developed. The coexistence of fragmented EGaIn and AgNW backbone, that is, a biphasic metallic composite (BMC), primarily supports the uniform and durable formation of target layers on stretchable substrates. The laser-induced photothermal reaction not only promotes the adhesion between the BMC layer and substrates but also alters the structure of laser-irradiated BMC. By controlling the degree of entanglement between fragmented EGaIn and AgNW, the initial conductivity and local gauge factor are regulated and the electrode becomes effectively insensitive to applied strain. As the configuration developed in this study is compatible with both regimes of electrodes, it can open new routes for the rapid creation of complex stretchable circuitry through a single process.
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Affiliation(s)
- Chulmin Cho
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- Mechatronics Research, Samsung Electronics, 1 Samsungjeonja-ro, Hwaseong-si, Gyeonggi-do, 18848, South Korea
| | - Wooseop Shin
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Minwoo Kim
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Junhyuk Bang
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Phillip Won
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Sukjoon Hong
- Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, Gyeonggi-do, 15588, South Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
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28
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Won D, Ko SH. The colour of stress. Nat Mater 2022; 21:997-998. [PMID: 36002720 DOI: 10.1038/s41563-022-01337-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Daeyeon Won
- Department of Mechanical Engineering, Seoul National University, Seoul, South Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul, South Korea.
- Institute of Engineering Research, Seoul National University, Seoul, South Korea.
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29
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Kim M, Oh J, Lee Y, Lee EH, Ko SH, Jeong JH, Park CH, Lee M. Delivery of self-replicating messenger RNA into the brain for the treatment of ischemic stroke. J Control Release 2022; 350:471-485. [PMID: 36041589 DOI: 10.1016/j.jconrel.2022.08.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 11/28/2022]
Abstract
Ischemic stroke is caused by the occlusion of cerebral arteries. In the ischemic stroke, ischemia-reperfusion injury increases the damage in the brain after reperfusion. In the previous study, heme oxygenase-1 (HO1) mRNA was delivered into the ischemic brain, showing that HO1-mRNA had higher therapeutic effect and less side-effect than HO1-plasmid (pHO1). However, mRNA is degraded faster than plasmid DNA reducing the duration of gene expression. In this study, self-replicating mRNA (Rep-mRNA) was developed using a replicon system from Venezuelan Equine Encephalitis virus to compensate this disadvantage of mRNA delivery. Deoxycholic acid-conjugated polyethylenimine (DA-PEI) was used as a carrier of the mRNA. The Rep-mRNA/DA-PEI complex had a size of around 90 nm and a zeta-potential of 33 mV. In the in vitro transfection assays, gene expression by the HO1-Rep-mRNA/DA-PEI complex persisted at least 14 days, while that by the HO1-mRNA/DA-PEI complex approached basal level at 3 days after transfection. Therapeutic effects of the HO1-Rep-mRNA/DA-PEI complexes were evaluated in the ischemic stroke animal models. The complexes were injected into the brain stereotaxically. HO1 expression by the HO1-Rep-mRNA/DA-PEI complex persisted at least 7 days after injection, but the pHO1/DA-PEI or HO1-mRNA/DA-PEI complex showed basal level of HO1-expression at 7 days after injection. Due to higher and longer expression of HO1, the apoptosis level and infarct size were decreased by the HO1-Rep-mRNA/DA-PEI complexes, compared with the pHO1/DA-PEI and HO1-mRNA/DA-PEI complex. These results suggest that HO1-Rep-mRNA/DA-PEI complex may have a potential as a long-lasting therapeutic system for the treatment of ischemic stroke.
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Affiliation(s)
- Minkyung Kim
- Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seondong-gu, Seoul 04763, Republic of Korea
| | - Jungju Oh
- Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seondong-gu, Seoul 04763, Republic of Korea
| | - Youngki Lee
- Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seondong-gu, Seoul 04763, Republic of Korea
| | - Eun-Hye Lee
- Hanyang Biomedical Research Institute, Hanyang University, Seoul 04763, Republic of Korea
| | - Seung Hwan Ko
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Ji Hoon Jeong
- College of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Chang Hwan Park
- Hanyang Biomedical Research Institute, Hanyang University, Seoul 04763, Republic of Korea; Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Republic of Korea; Department of Microbiology, College of Medicine, Hanyang University, Seoul 04763, Republic of Korea.
| | - Minhyung Lee
- Department of Bioengineering, College of Engineering, Hanyang University, 222 Wangsimni-ro, Seondong-gu, Seoul 04763, Republic of Korea.
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30
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Song S, Um SH, Park J, Ha I, Lee J, Kim S, Lee H, Cheon CH, Ko SH, Kim YC, Jeon H. Rapid Synthesis of Multifunctional Apatite via the Laser-Induced Hydrothermal Process. ACS Nano 2022; 16:12840-12851. [PMID: 35950962 DOI: 10.1021/acsnano.2c05110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Synthetic biomaterials are used to overcome the limited quantity of human-derived biomaterials and to impart additional biofunctionality. Although numerous synthetic processes have been developed using various phases and methods, currently commonly used processes have some issues, such as a long process time and difficulties with extensive size control and high-concentration metal ion substitution to achieve additional functionality. Herein, we introduce a rapid synthesis method using a laser-induced hydrothermal process. Based on the thermal interaction between the laser pulses and titanium, which was used as a thermal reservoir, hydroxyapatite particles ranging from nanometer to micrometer scale could be synthesized in seconds. Further, this method enabled selective metal ion substitution into the apatite matrix with a controllable concentration. We calculated the maximum temperature achieved by laser irradiation at the surface of the thermal reservoir based on the validation of three simplification assumptions. Subsequent linear regression analysis showed that laser-induced hydrothermal synthesis follows an Arrhenius chemical reaction. Hydroxyapatite and Mg2+-, Sr2+-, and Zn2+-substituted apatite powders promoted bone cell attachment and proliferation ability due to ion release from the hydroxyapatite and the selective ion-substituted apatite powders, which had a low crystallinity and relatively high solubility. Laser-induced hydrothermal synthesis is expected to become a powerful ceramic material synthesis technology.
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Affiliation(s)
- Sangmin Song
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Seung-Hoon Um
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Jaeho Park
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Materials science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea
| | - Inho Ha
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Jaehong Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Seongchan Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Hyojin Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Cheol-Hong Cheon
- Department of Chemistry, Korea University, Seoul, 02841, Republic of Korea
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Yu-Chan Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Hojeong Jeon
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
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31
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Lee J, Jung Y, Lee M, Hwang JS, Guo J, Shin W, Min J, Pyun KR, Lee H, Lee Y, Shiomi J, Kim YJ, Kim BW, Ko SH. Biomimetic reconstruction of butterfly wing scale nanostructures for radiative cooling and structural coloration. Nanoscale Horiz 2022; 7:1054-1064. [PMID: 35775456 DOI: 10.1039/d2nh00166g] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A great number of butterfly species in the warmer climate have evolved to exhibit fascinating optical properties on their wing scales which can both regulate the wing temperature and exhibit structural coloring in order to increase their chances of survival. In particular, the Archaeoprepona demophon dorsal wing demonstrates notable radiative cooling performance and iridescent colors based on the nanostructure of the wing scale that can be characterized by the nanoporous matrix with the periodic nanograting structure on the top matrix surface. Inspired by the natural species, we demonstrate a multifunctional biomimetic film that reconstructs the nanostructure of the Archaeoprepona demophon wing scales to replicate the radiative cooling and structural coloring functionalities. We resorted to the SiO2 sacrificial template-based solution process to mimic the random porous structure and laser-interference lithography to reproduce the nanograting architecture of the butterfly wing scale. As a result, the biomimetic structure of the nanograted surface on top of the porous film demonstrated desirable heat transfer and optical properties for outstanding radiative cooling performance and iridescent structural coloring. In this regard, the film is capable of inducing the maximum temperature drop of 8.45 °C, and the color gamut of the biomimetic film can cover 91.8% of the standardized color profile (sRGB).
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Affiliation(s)
- Jinwoo Lee
- George W. Woodruff School of Mechanical Engineering, Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
| | - MinJae Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Advanced Materials Research Team, Hyundai Motor Group, 37, Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do, 16082, South Korea.
| | - June Sik Hwang
- Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yusung-gu, Daejeon 34141, South Korea
| | - Jiang Guo
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Wooseop Shin
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
| | - JinKi Min
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
| | - Kyung Rok Pyun
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
| | - Huseung Lee
- Department of Mechanical and Materials Engineering Education, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon, 34134, South Korea
| | - Yaerim Lee
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Junichiro Shiomi
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Young-Jin Kim
- Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yusung-gu, Daejeon 34141, South Korea
| | - Byung-Wook Kim
- Advanced Materials Research Team, Hyundai Motor Group, 37, Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do, 16082, South Korea.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
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Won D, Kim J, Choi J, Kim H, Han S, Ha I, Bang J, Kim KK, Lee Y, Kim TS, Park JH, Kim CY, Ko SH. Digital selective transformation and patterning of highly conductive hydrogel bioelectronics by laser-induced phase separation. Sci Adv 2022; 8:eabo3209. [PMID: 35675404 PMCID: PMC9177068 DOI: 10.1126/sciadv.abo3209] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 04/21/2022] [Indexed: 05/19/2023]
Abstract
The patterning of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) hydrogels with excellent electrical property and spatial resolution is a challenge for bioelectronic applications. However, most PEDOT:PSS hydrogels are fabricated by conventional manufacturing processes such as photolithography, inkjet printing, and screen printing with complex fabrication steps or low spatial resolution. Moreover, the additives used for fabricating PEDOT:PSS hydrogels are mostly cytotoxic, thus requiring days of detoxification. Here, we developed a previously unexplored ultrafast and biocompatible digital patterning process for PEDOT:PSS hydrogel via phase separation induced by a laser. We enhanced the electrical properties and aqueous stability of PEDOT:PSS by selective laser scanning, which allowed the transformation of PEDOT:PSS into water-stable hydrogels. PEDOT:PSS hydrogels showed high electrical conductivity of 670 S/cm with 6-μm resolution in water. Furthermore, electrochemical properties were maintained even after 6 months in a physiological environment. We further demonstrated stable neural signal recording and stimulation with hydrogel electrodes fabricated by laser.
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Affiliation(s)
- Daeyeon Won
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jin Kim
- Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- College of Veterinary Medicine, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Joonhwa Choi
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - HyeongJun Kim
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Seonggeun Han
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Inho Ha
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Junhyuk Bang
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kyun Kyu Kim
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Youngseok Lee
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Taek-Soo Kim
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Jae-Hak Park
- Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - C-Yoon Kim
- College of Veterinary Medicine, Konkuk University, 120, Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
- Corresponding author. (S.H.K.); (C.-Y.K.)
| | - Seung Hwan Ko
- Soft Robotics Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, Seoul 08826, Republic of Korea
- Corresponding author. (S.H.K.); (C.-Y.K.)
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Lee E, Kim M, Ko SH, Lee M, Park C. The primary astrocytic mitochondrial transplantation ameliorates ischemic stroke. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.0r802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Metal-oxide nanomaterials (MONs) have gained considerable interest in the construction of flexible/wearable sensors due to their tunable band gap, low cost, large specific area, and ease of manufacturing. Furthermore, MONs are in high demand for applications, such as gas leakage alarms, environmental protection, health tracking, and smart devices integrated with another system. In this Review, we introduce a comprehensive investigation of factors to boost the sensitivity of MON-based sensors in environmental indicators and health monitoring. Finally, the challenges and perspectives of MON-based flexible/wearable sensors are considered.
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Affiliation(s)
- Yeosang Yoon
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu,
Seoul 08826, Korea
| | - Phuoc Loc Truong
- Laser
and Thermal Engineering Lab, Department of Mechanical Engineering, Gachon University, Seongnam 13120, Korea
| | - Daeho Lee
- Laser
and Thermal Engineering Lab, Department of Mechanical Engineering, Gachon University, Seongnam 13120, Korea
| | - Seung Hwan Ko
- Applied
Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu,
Seoul 08826, Korea
- Institute
of Advanced Machinery and Design (SNU-IAMD), Seoul National University, Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
- Institute
of Engineering Research, Seoul National
University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
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35
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Kim J, Kim MS, Lee Y, Kim SY, Sung YE, Ko SH. Hierarchically Structured Conductive Polymer Binders with Silver Nanowires for High-Performance Silicon Anodes in Lithium-Ion Batteries. ACS Appl Mater Interfaces 2022; 14:17340-17347. [PMID: 35385265 DOI: 10.1021/acsami.2c00844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Silicon (Si) anodes in lithium-ion batteries (LIBs) suffer from huge volume changes that lead to a rapid capacity decrease and short cycle life. A conductive binder can be a key factor to overcome this issue, maintaining continuous electron paths under pulverization of Si. Herein, composites of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and poly(vinyl alcohol) (PVA) are augmented with poly(ethylene glycol) (PEG) and poly(ethylene oxide) (PEO) as a binder for Si anodes, which forms hierarchical structures due to different chain lengths of PEG and PEO. The integration of PEG and PEO imparts higher electrical conductivity (∼40%) and stretchability (∼60%) through densely spread hydrogen bonding and cross-linking, compared to conductive polymer binders with PEO or PEG. Further, a silver nanowire (AgNW) network combined with the polymer binder supplies an effective three-dimensional (3D) electrical path, sufficient void space to buffer the volume changes, and highly adhesive interaction with the current collector. The fabricated Si anode demonstrates a higher specific capacity of 1066 mAh g-1 at 0.8 A g-1 after 100 cycles and improved rate capability.
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Affiliation(s)
- Jaewon Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Min-Seob Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Youngseok Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Shin-Yeong Kim
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Yung-Eun Sung
- Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea
- School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University, Seoul 08826, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, Seoul 08826, Republic of Korea
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36
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Kim HB, Shim JK, Ko SH, Kim HR, Lee CH, Kwak YL. Effect of iron deficiency without anaemia on days alive and out of hospital in patients undergoing valvular heart surgery. Anaesthesia 2022; 77:562-569. [PMID: 35262180 DOI: 10.1111/anae.15681] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2022] [Indexed: 12/01/2022]
Abstract
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127-141 [120-172]) g.l-1 , 143 (133-150 [120-179]) g.l-1 , p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77-82 [9-85]) days vs. 81 (79-83 [0-85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.
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Affiliation(s)
- H B Kim
- Department of Anaesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - J K Shim
- Department of Anaesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - S H Ko
- Department of Anaesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - H R Kim
- Biostatistics Collaboration Unit, Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - C H Lee
- Department of Anaesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Y L Kwak
- Department of Anaesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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Song S, Kim KY, Lee SH, Kim KK, Lee K, Lee W, Jeon H, Ko SH. Recent Advances in 1D Nanomaterial‐Based Bioelectronics for Healthcare Applications. Advanced NanoBiomed Research 2022. [DOI: 10.1002/anbr.202270025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Sangmin Song
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Kyung Yeun Kim
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Sun Hee Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Kyun Kyu Kim
- Department of Chemical Engineering Stanford University Stanford CA 94305 USA
| | - Kyungwoo Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Wonryung Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Hojeong Jeon
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
- KU-KIST Graduate School of Converging Science and Technology Korea University 145, Anam-ro Seongbuk-gu Seoul 02841 Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research Seoul National University Seoul 08826 Korea
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38
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Kim C, An K, Kang M, Won P, Park JJ, Cho KH, Ko SH, Ju BK, Kang KT. Facile fabrication of flexible metal grid transparent electrode using inkjet-printed dot array as sacrificial layer. Sci Rep 2022; 12:1572. [PMID: 35091581 PMCID: PMC8799687 DOI: 10.1038/s41598-022-05312-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 12/29/2021] [Indexed: 11/09/2022] Open
Abstract
In this study, we introduce a flexible metal grid transparent electrode fabricated using a lift-off process. This transparent electrode consisting of metal thin film with punched-like pattern by hole array was fabricated with 8 um separations. The separation of inkjet-printed etching resistant ink droplets was controlled in order to investigate the relationship between its electrical and optical properties of the electrodes. The aluminum areal density was defined to predict the electrical and optical properties of different arrays. A high and uniform transmittance spectrum appears to extend broadly into the UV region. The figure of merit of the transparent electrode was investigated in order to determine its performance as a transparent electrode. Moreover, there was no significant change in the resistance after 7000 bending cycles, indicating that the array conductor had superior stability. We also demonstrate transparent touch screen panels fabricated using the transparent electrode.
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Affiliation(s)
- Chaewon Kim
- Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), Sangnok-gu, Ansan-si, 15588, Korea.,Display and Nanosystem Laboratory, School of Electrical Engineering, Korea University, Seoul, 02841, Korea
| | - Kunsik An
- Department of Mechatronics Engineering, Konkuk University, Chungju, 27478, South Korea
| | - Mingu Kang
- Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), Sangnok-gu, Ansan-si, 15588, Korea
| | - Phillip Won
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jung-Jae Park
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Kwan Hyun Cho
- Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), Sangnok-gu, Ansan-si, 15588, Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Byeong-Kwon Ju
- Display and Nanosystem Laboratory, School of Electrical Engineering, Korea University, Seoul, 02841, Korea.
| | - Kyung-Tae Kang
- Digital Transformation R&D Department, Korea Institute of Industrial Technology (KITECH), Sangnok-gu, Ansan-si, 15588, Korea.
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39
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Bang J, Jung Y, Kim H, Kim D, Cho M, Ko SH. Multi-Bandgap Monolithic Metal Nanowire Percolation Network Sensor Integration by Reversible Selective Laser-Induced Redox. Nanomicro Lett 2022; 14:49. [PMID: 35076794 PMCID: PMC8789997 DOI: 10.1007/s40820-021-00786-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/07/2021] [Indexed: 05/05/2023]
Abstract
Active electronics are usually composed of semiconductor and metal electrodes which are connected by multiple vacuum deposition steps and photolithography patterning. However, the presence of interface of dissimilar material between semiconductor and metal electrode makes various problems in electrical contacts and mechanical failure. The ideal electronics should not have defective interfaces of dissimilar materials. In this study, we developed a novel method to fabricate active electronic components in a monolithic seamless fashion where both metal and semiconductor can be prepared from the same monolith material without creating a semiconductor-metal interface by reversible selective laser-induced redox (rSLIR) method. Furthermore, rSLIR can control the oxidation state of transition metal (Cu) to yield semiconductors with two different bandgap states (Cu2O and CuO with bandgaps of 2.1 and 1.2 eV, respectively), which may allow multifunctional sensors with multiple bandgaps from the same materials. This novel method enables the seamless integration of single-phase Cu, Cu2O, and CuO, simultaneously while allowing reversible, selective conversion between oxidation states by simply shining laser light. Moreover, we fabricated a flexible monolithic metal-semiconductor-metal multispectral photodetector that can detect multiple wavelengths. The unique monolithic characteristics of rSLIR process can provide next-generation electronics fabrication method overcoming the limitation of conventional photolithography methods.
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Affiliation(s)
- Junhyuk Bang
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Yeongju Jung
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Hyungjun Kim
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Dongkwan Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Maenghyo Cho
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea.
- Institute of Advanced Machines and Design, Institute of Engineering Research, Seoul National University, Seoul, 08826, Republic of Korea.
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40
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Han S, Kim J, Lee Y, Bang J, Kim CG, Choi J, Min J, Ha I, Yoon Y, Yun CH, Cruz M, Wiley BJ, Ko SH. Transparent Air Filters with Active Thermal Sterilization. Nano Lett 2022; 22:524-532. [PMID: 34665632 DOI: 10.1021/acs.nanolett.1c02737] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The worldwide proliferation of COVID-19 poses the urgent need for sterilizable and transparent air filters to inhibit virus transmission while retaining ease of communication. Here, we introduce copper nanowires to fabricate transparent and self-sterilizable air filters. Copper nanowire air filter (CNAF) allowed visible light penetration, thereby can exhibit facial expressions, helpful for better communication. CNAF effectively captured particulate matter (PM) by mechanical and electrostatic filtration mechanisms. The temperature of CNAF could be controlled by Joule-heating up to 100 °C with thermal stability. CNAF successfully inhibited the growth of E. coli because of the oligodynamic effect of copper. With heat sterilization, the antibacterial efficiency against G. anodireducens was greatly improved up to 99.3% within 10 min. CNAF showed high reusability with stable filtration efficiency and thermal antibacterial efficacy after five repeated uses. Our result suggests an alternative form of active antimicrobial air filter in preparation for the current and future pandemic situations.
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Affiliation(s)
- Seonggeun Han
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jaewon Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Youngseok Lee
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Junhyuk Bang
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Cheol Gyun Kim
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Junhwa Choi
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jinki Min
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Inho Ha
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Yeosang Yoon
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Cheol-Heui Yun
- Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Mutya Cruz
- Department of Chemistry, Duke University, 124 Science Drive, Box 90354, Durham, North Carolina 27708, United States
| | - Benjamin J Wiley
- Department of Chemistry, Duke University, 124 Science Drive, Box 90354, Durham, North Carolina 27708, United States
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
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Khor SM, Choi J, Won P, Ko SH. Challenges and Strategies in Developing an Enzymatic Wearable Sweat Glucose Biosensor as a Practical Point-Of-Care Monitoring Tool for Type II Diabetes. Nanomaterials (Basel) 2022; 12:221. [PMID: 35055239 PMCID: PMC8781831 DOI: 10.3390/nano12020221] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/07/2022] [Accepted: 01/08/2022] [Indexed: 01/27/2023]
Abstract
Recently, several studies have been conducted on wearable biosensors. Despite being skin-adhesive and mountable diagnostic devices, flexible biosensor patches cannot truly be considered wearable biosensors if they need to be connected to external instruments/processors to provide meaningful data/readings. A realistic and usable wearable biosensor should be self-contained, with a fully integrated device framework carefully designed and configured to provide reliable and intelligent diagnostics. There are several major challenges to achieving continuous sweat monitoring in real time for the systematic and effective management of type II diabetes (e.g., prevention, screening, monitoring, and treatment) through wearable sweat glucose biosensors. Consequently, further in-depth research regarding the exact interrelationship between active or passive sweat glucose and blood glucose is required to assess the applicability of wearable glucose biosensors in functional health monitoring. This review provides some useful insights that can enable effective critical studies of these unresolved issues. In this review, we first classify wearable glucose biosensors based on their signal transduction, their respective challenges, and the advanced strategies required to overcome them. Subsequently, the challenges and limitations of enzymatic and non-enzymatic wearable glucose biosensors are discussed and compared. Ten basic criteria to be considered and fulfilled in the development of a suitable, workable, and wearable sweat-based glucose biosensor are listed, based on scientific reports from the last five years. We conclude with our outlook for the controllable, well-defined, and non-invasive monitoring of epidermal glucose for maximum diagnostic potential in the effective management of type II diabetes.
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Affiliation(s)
- Sook Mei Khor
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea; (S.M.K.); (J.C.)
- Department of Chemistry, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Joonhwa Choi
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea; (S.M.K.); (J.C.)
| | - Phillip Won
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA;
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea; (S.M.K.); (J.C.)
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, Seoul 08826, Korea
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Song S, Kim KY, Lee SH, Kim KK, Lee K, Lee W, Jeon H, Ko SH. Recent Advances in 1D Nanomaterial‐Based Bioelectronics for Healthcare Applications. Advanced NanoBiomed Research 2021. [DOI: 10.1002/anbr.202100111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Sangmin Song
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Kyung Yeun Kim
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Sun Hee Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Kyun Kyu Kim
- Department of Chemical Engineering Stanford University Stanford CA 94305 USA
| | - Kyungwoo Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Wonryung Lee
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
| | - Hojeong Jeon
- Center for Biomaterials Biomedical Research Institute Korea Institute of Science and Technology (KIST) 5, Hwarang-ro 14-gil Seongbuk-gu Seoul 02792 Korea
- KU-KIST Graduate School of Converging Science and Technology Korea University 145, Anam-ro Seongbuk-gu Seoul 02841 Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak-ro Gwanak-gu Seoul 151-742 Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research Seoul National University Seoul 08826 Korea
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Yoon M, Yoo K, Seo B, Ko SH, Lim CS. Development of Low-Shrink Epoxy Putty to Solve Appearance-Quality Defects of Carbon-Fiber-Reinforced Plastic Automotive Exterior Parts. Materials (Basel) 2021; 14:ma14216419. [PMID: 34771945 PMCID: PMC8585267 DOI: 10.3390/ma14216419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/13/2021] [Accepted: 10/20/2021] [Indexed: 11/21/2022]
Abstract
In this study, epoxy putties with novel compositions were developed for the filling of structural voids in carbon-fiber-reinforced plastics (CFRPs), which are used to fabricate automotive parts. Two constituent solutions—one consisting of epoxy resins and the other consisting of a hardener—were formulated, mixed, and then coated on CFRP surfaces, followed by curing. The surfaces were then evaluated to determine the shrinkage rates (calculated based on the liquid densities and cured mixtures), adhesion properties (determined by a peel test), and color differences (measured with a colorimeter) of the synthesized putties. The last two properties were compared with those of the commercially available putties to ascertain the thermal resistance of the developed putties. The results indicated that the synthesized epoxy putties were more strongly adhesive and exhibited less difference in color. Furthermore, after thermal impact, both the adhesive properties and color stabilities of the synthesized epoxy putties were found to be superior to those of the commercial putty.
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Affiliation(s)
- Manseok Yoon
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Korea; (M.Y.); (S.H.K.)
| | | | - Bongkuk Seo
- Research Center for Advanced Specialty Chemicals, Korea Research Institute of Chemical Technology, 45, Jongga-ro, Yugok-dong, Jung-gu, Ulsan 44412, Korea;
| | - Seung Hwan Ko
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Korea; (M.Y.); (S.H.K.)
| | - Choong-Sun Lim
- Research Center for Advanced Specialty Chemicals, Korea Research Institute of Chemical Technology, 45, Jongga-ro, Yugok-dong, Jung-gu, Ulsan 44412, Korea;
- Correspondence: ; Tel.: +82-52-241-6021
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Shin J, Jeong S, Kim J, Choi YY, Choi J, Lee JG, Kim S, Kim M, Rho Y, Hong S, Choi JI, Grigoropoulos CP, Ko SH. Dynamic Pore Modulation of Stretchable Electrospun Nanofiber Filter for Adaptive Machine Learned Respiratory Protection. ACS Nano 2021; 15:15730-15740. [PMID: 34585584 DOI: 10.1021/acsnano.1c06204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The recent emergence of highly contagious respiratory disease and the underlying issues of worldwide air pollution jointly heighten the importance of the personal respirator. However, the incongruence between the dynamic environment and nonadaptive respirators imposes physiological and psychological adverse effects, which hinder the public dissemination of respirators. To address this issue, we introduce adaptive respiratory protection based on a dynamic air filter (DAF) driven by machine learning (ML) algorithms. The stretchable elastomer fiber membrane of the DAF affords immediate adjustment of filtration characteristics through active rescaling of the micropores by simple pneumatic control, enabling seamless and constructive transition of filtration characteristics. The resultant DAF-respirator (DAF-R), made possible by ML algorithms, successfully demonstrates real-time predictive adapting maneuvers, enabling personalizable and continuously optimized respiratory protection under changing circumstances.
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Affiliation(s)
- Jaeho Shin
- Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Seongmin Jeong
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Jinmo Kim
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Yun Young Choi
- Department of Computational Science and Engineering, Yonsei University, Yonsei-ro 50, Seojdamun-gu, Seoul 03722, Korea
| | - Joonhwa Choi
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Jae Gun Lee
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Seongyoon Kim
- Department of Computational Science and Engineering, Yonsei University, Yonsei-ro 50, Seojdamun-gu, Seoul 03722, Korea
| | - Munju Kim
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Yoonsoo Rho
- Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Sukjoon Hong
- Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, Gyeonggi-do 15588, Korea
| | - Jung-Il Choi
- Department of Computational Science and Engineering, Yonsei University, Yonsei-ro 50, Seojdamun-gu, Seoul 03722, Korea
| | - Costas P Grigoropoulos
- Department of Mechanical Engineering, University of California, Berkeley, California 94720, United States
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
- Institute of Advanced Machines and Design/Institute of Engineering Research, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
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Ha I, Kim M, Kim KK, Hong S, Cho H, Kwon J, Han S, Yoon Y, Won P, Ko SH. Reversible, Selective, Ultrawide-Range Variable Stiffness Control by Spatial Micro-Water Molecule Manipulation. Adv Sci (Weinh) 2021; 8:e2102536. [PMID: 34449132 PMCID: PMC8529442 DOI: 10.1002/advs.202102536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/15/2021] [Indexed: 05/03/2023]
Abstract
Evolution has decided to gift an articular structure to vertebrates, but not to invertebrates, owing to their distinct survival strategies. An articular structure permits kinematic motion in creatures. However, it is inappropriate for creatures whose survival strategy depends on the high deformability of their body. Accordingly, a material in which the presence of the articular structure can be altered, allowing the use of two contradictory strategies, will be advantageous in diverse dynamic applications. Herein, spatial micro-water molecule manipulation, termed engineering on variable occupation of water (EVO), that is used to realize a material with dual mechanical modes that exhibit extreme differences in stiffness is introduced. A transparent and homogeneous soft material (110 kPa) reversibly converts to an opaque material embodying a mechanical gradient (ranging from 1 GPa to 1 MPa) by on-demand switching. Intensive theoretical analysis of EVO yields the design of spatial transformation scheme. The EVO gel accomplishes kinematic motion planning and shows great promise for multimodal kinematics. This approach paves the way for the development and application of smart functional materials.
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Affiliation(s)
- Inho Ha
- Soft Robotics Research CenterSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Minwoo Kim
- Soft Robotics Research CenterSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Kyun Kyu Kim
- Soft Robotics Research CenterSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Sukjoon Hong
- Optical Nanoprocessing LabDepartment of Mechanical EngineeringHanyang University55 Hanyangdaehak‐ro, Sangnok‐guAnsan15588Korea
| | - Hyunmin Cho
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Jinhyeong Kwon
- Intelligent Manufacturing System R&D DepartmentKorea Institute of Industrial Technology89 Yangdaegiro‐gil, Ipjang‐myeon, Seobuk‐guCheonanChungcheongnam‐do31056Korea
| | - Seonggeun Han
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Yeosang Yoon
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Phillip Won
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
| | - Seung Hwan Ko
- Soft Robotics Research CenterSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
- Applied Nano and Thermal Science LabDepartment of Mechanical EngineeringSeoul National University1 Gwanak‐ro, Gwanak‐guSeoul08826Korea
- Institute of Advanced Machines and Design/Institute of Engineering ResearchSeoul National UniversitySeoul08826Korea
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46
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Kim KK, Choi J, Ko SH. Energy Harvesting Untethered Soft Electronic Devices (Adv. Healthcare Mater. 17/2021). Adv Healthc Mater 2021. [DOI: 10.1002/adhm.202170077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Advances in wearable and stretchable electronic technologies have yielded a wide range of electronic devices that can be conformably worn by, or implanted in humans to measure physiological signals. Moreover, various cutting-edge technologies for battery-free electronic devices have led to advances in healthcare devices that can continuously measure long-term biosignals for advanced human-machine interface and clinical diagnostics. This report presents the recent progress in battery-less, wearable devices using a wide range of energy harvesting sources, such as electromagnetic energy, mechanical energy, and biofuels. Additionally, this report also discusses the principles and working mechanisms of near/far-field communications, triboelectric, thermoelectric, and biofuel technologies.
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Affiliation(s)
- Kyun Kyu Kim
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak‐ro, Gwanak‐gu Seoul 151‐742 Korea
| | - Joonhwa Choi
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak‐ro, Gwanak‐gu Seoul 151‐742 Korea
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab Department of Mechanical Engineering Seoul National University 1 Gwanak‐ro, Gwanak‐gu Seoul 151‐742 Korea
- Institute of Advanced Machines and Design Seoul National University Seoul 08826 Korea
- Institute of Engineering Research Seoul National University Seoul 08826 Korea
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48
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Koylan S, Tunca S, Polat G, Durukan MB, Kim D, Kalay YE, Ko SH, Unalan HE. Highly stable silver-platinum core-shell nanowires for H 2O 2 detection. Nanoscale 2021; 13:13129-13141. [PMID: 34477796 DOI: 10.1039/d1nr01976g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Silver nanowire (Ag NW) networks have great potential to replace commercial transparent conducting oxides due to their superior properties in conjunction with their competitive cost, availability and mechanical flexibility. However, there are still challenges to overcome for the large scale utilization of Ag NWs in devices due to oxidation/sulfidation of NWs, which leads to performance loss. Here, we develop a solution-based strategy to deposit a thin platinum (Pt) shell layer (15 nm) onto Ag NWs to improve their chemical, environmental and electrochemical stabilities. Environmental and thermal stabilities of the core-shell NW networks were monitored under different relative humidity conditions (RH of 43, 75 and 85%) and temperature settings (75 °C for 120 hours and 150 °C for 40 hours) and compared to those of bare Ag NWs. Afterwards, stability of core-shell NW networks in hydrogen peroxide was investigated and compared to that of bare Ag NW networks. The potential window for electrochemical stability of the Ag NW networks was broadened to 0-1 V (vs. Ag/AgCl) upon Pt deposition, while bare Ag NWs were stable only in the 0-0.6 V range. Moreover, Ag-Pt core-shell NWs were used for the detection of hydrogen peroxide, where a high sensitivity of 0.04 μA μM-1 over a wide linear range of concentrations (16.6-990.1 μM) with a low detection limit (10.95 μM) was obtained for the fabricated sensors. All in all, this highly effective and simple strategy to improve the stability of Ag NWs will certainly open new avenues for their large-scale utilization in various electrochemical and sensing devices.
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Affiliation(s)
- Serkan Koylan
- Department of Metallurgical and Materials Engineering, Middle East Technical University (METU), 06800, Ankara, Turkey.
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Kim H, Choi J, Kim KK, Won P, Hong S, Ko SH. Biomimetic chameleon soft robot with artificial crypsis and disruptive coloration skin. Nat Commun 2021; 12:4658. [PMID: 34376680 PMCID: PMC8355336 DOI: 10.1038/s41467-021-24916-w] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 07/12/2021] [Indexed: 11/09/2022] Open
Abstract
Development of an artificial camouflage at a complete device level remains a vastly challenging task, especially under the aim of achieving more advanced and natural camouflage characteristics via high-resolution camouflage patterns. Our strategy is to integrate a thermochromic liquid crystal layer with the vertically stacked, patterned silver nanowire heaters in a multilayer structure to overcome the limitations of the conventional lateral pixelated scheme through the superposition of the heater-induced temperature profiles. At the same time, the weaknesses of thermochromic camouflage schemes are resolved in this study by utilizing the temperature-dependent resistance of the silver nanowire network as the process variable of the active control system. Combined with the active control system and sensing units, the complete device chameleon model successfully retrieves the local background color and matches its surface color instantaneously with natural transition characteristics to be a competent option for a next-generation artificial camouflage. Realizing an artificial camouflage device with a high spatial resolution by adapting to the surrounding environment in real-time is a challenging task, mainly associated with device fabrication and integration with sensor and control circuits. To overcome these limitations, the authors utilize thermochromic liquid crystal ink that reacts to the feedback control system of the vertically stacked silver nanowire heater.
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Affiliation(s)
- Hyeonseok Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul, Korea
| | - Joonhwa Choi
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul, Korea
| | - Kyun Kyu Kim
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul, Korea
| | - Phillip Won
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul, Korea
| | - Sukjoon Hong
- Optical Nanoprocessing Lab, Department of Mechanical Engineering, BK21 FOUR ERICA-ACE Center, Hanyang University, Ansan, Gyeonggi-do, Korea.
| | - Seung Hwan Ko
- Applied Nano and Thermal Science Lab, Department of Mechanical Engineering, Seoul National University, Seoul, Korea. .,Institute of Advanced Machinery and Design (SNU-IAMD)/Institute of Engineering Research, Seoul National University, Seoul, Korea.
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Abstract
Soft wearable electronics are rapidly developing through exploration of new materials, fabrication approaches, and design concepts. Although there have been many efforts for decades, a resurgence of interest in liquid metals (LMs) for sensing and wiring functional properties of materials in soft wearable electronics has brought great advances in wearable electronics and materials. Various forms of LMs enable many routes to fabricate flexible and stretchable sensors, circuits, and functional wearables with many desirable properties. This review article presents a systematic overview of recent progresses in LM-enabled wearable electronics that have been achieved through material innovations and the discovery of new fabrication approaches and design architectures. We also present applications of wearable LM technologies for physiological sensing, activity tracking, and energy harvesting. Finally, we discuss a perspective on future opportunities and challenges for wearable LM electronics as this field continues to grow.
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Affiliation(s)
- Phillip Won
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Seongmin Jeong
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
| | - Carmel Majidi
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Seung Hwan Ko
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
- Institute of Advanced Machines and Design / Institute of Engineering Research, Seoul National University, Seoul 08826, Korea
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