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Dorrian RM, Leonard AV, Lauto A. Millimetric devices for nerve stimulation: a promising path towards miniaturization. Neural Regen Res 2024; 19:1702-1706. [PMID: 38103235 PMCID: PMC10960286 DOI: 10.4103/1673-5374.389627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/21/2023] [Accepted: 10/19/2023] [Indexed: 12/18/2023] Open
Abstract
Nerve stimulation is a rapidly developing field, demonstrating positive outcomes across several conditions. Despite potential benefits, current nerve stimulation devices are large, complicated, and are powered via implanted pulse generators. These factors necessitate invasive surgical implantation and limit potential applications. Reducing nerve stimulation devices to millimetric sizes would make these interventions less invasive and facilitate broader therapeutic applications. However, device miniaturization presents a serious engineering challenge. This review presents significant advancements from several groups that have overcome this challenge and developed millimetric-sized nerve stimulation devices. These are based on antennas, mini-coils, magneto-electric and opto-electronic materials, or receive ultrasound power. We highlight key design elements, findings from pilot studies, and present several considerations for future applications of these devices.
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Affiliation(s)
- Ryan M. Dorrian
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Anna V. Leonard
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
| | - Antonio Lauto
- School of Science, Western Sydney University, Penrith, NSW, Australia
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2
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Jo D, Lee H, Jang Y, Oh P, Kwon Y. The Development of a New Vagus Nerve Simulation Electroceutical to Improve the Signal Attenuation in a Living Implant Environment. SENSORS (BASEL, SWITZERLAND) 2024; 24:3172. [PMID: 38794024 PMCID: PMC11125165 DOI: 10.3390/s24103172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/14/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
An electroceutical is a medical device that uses electrical signals to control biological functions. It can be inserted into the human body as an implant and has several crucial advantages over conventional medicines for certain diseases. This research develops a new vagus nerve simulation (VNS) electroceutical through an innovative approach to overcome the communication limitations of existing devices. A phased array antenna with a better communication performance was developed and applied to the electroceutical prototype. In order to effectively respond to changes in communication signals, we developed the steering algorithm and firmware, and designed the smart communication protocol that operates at a low power that is safe for the patients. This protocol is intended to improve a communication sensitivity related to the transmission and reception distance. Based on this technical approach, the heightened effectiveness and safety of the prototype have been ascertained, with the actual clinical tests using live animals. We confirmed the signal attenuation performance to be excellent, and a smooth communication was achieved even at a distance of 7 m. The prototype showed a much wider communication range than any other existing products. Through this, it is conceivable that various problems due to space constraints can be resolved, hence presenting many benefits to the patients whose last resort to the disease is the VNS electroceutical.
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Affiliation(s)
- Daeil Jo
- Department of Industrial Engineering, Ajou University, Suwon 16499, Republic of Korea;
- Oceans Bio Co., Ltd., Seoul 04303, Republic of Korea; (H.L.); (Y.J.)
| | - Hyunung Lee
- Oceans Bio Co., Ltd., Seoul 04303, Republic of Korea; (H.L.); (Y.J.)
| | - Youlim Jang
- Oceans Bio Co., Ltd., Seoul 04303, Republic of Korea; (H.L.); (Y.J.)
| | - Paul Oh
- Department of Mechanical Engineering, University of Nevada-Las Vegas, Las Vegas, NV 89154, USA;
| | - Yongjin Kwon
- Department of Industrial Engineering, Ajou University, Suwon 16499, Republic of Korea;
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3
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Benbuk A, Gulick D, Moniz-Garcia D, Liu S, Quinones-Hinojosa A, Christen JB. Wireless Stimulation of Motor Cortex Through a Collagen Dura Substitute Using an Ultra-Thin Implant Fabricated on Parylene/PDMS. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2024; 18:334-346. [PMID: 37910421 PMCID: PMC11080957 DOI: 10.1109/tbcas.2023.3329447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
We present the design, fabrication, and in vivo testing of an ultra-thin (100 μm) wireless and battery-free implant for stimulation of the brain's cortex. The implant is fabricated on a flexible and transparent parylene/PDMS substrate, and it is miniaturized to dimensions of 15.6 × 6.6 mm 2. The frequency and pulse width of the monophasic voltage pulses are determined through On-Off keying (OOK) modulation of a wireless transmission at 2.45 GHz. Furthermore, the implant triggered a motor response in vivo when tested in 6 rodents. Limb response was observed by wireless stimulation of the brain's motor cortex through an FDA-approved collagen dura substitute that was placed on the dura in the craniotomy site, with no direct contact between the implant's electrodes and the brain's cortical surface. Therefore, the wireless stimulation method reported herein enables the concept of an e-dura substitute, where wireless electronics can be integrated onto a conventional dura substitute to augment its therapeutic function and administer any desired stimulation protocol without the need for post-surgical intervention for battery replacement or reprogramming stimulation parameters.
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4
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Mereu F, Cordella F, Paolini R, Scarpelli A, Demofonti A, Zollo L, Gruppioni E. A Sensory Feedback Neural Stimulator Prototype for Both Implantable and Wearable Applications. MICROMACHINES 2024; 15:480. [PMID: 38675291 PMCID: PMC11051761 DOI: 10.3390/mi15040480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/23/2024] [Accepted: 03/29/2024] [Indexed: 04/28/2024]
Abstract
The restoration of sensory feedback is one of the current challenges in the field of prosthetics. This work, following the analysis of the various types of sensory feedback, aims to present a prototype device that could be used both for implantable applications to perform PNS and for wearable applications, performing TENS, to restore sensory feedback. The two systems are composed of three electronic boards that are presented in detail, as well as the bench tests carried out. To the authors' best knowledge, this work presents the first device that can be used in a dual scenario for restoring sensory feedback. Both the implantable and wearable versions respected the expected values regarding the stimulation parameters. In its implantable version, the proposed system allows simultaneous and independent stimulation of 30 channels. Furthermore, the capacity of the wearable version to elicit somatic sensations was evaluated on healthy participants demonstrating performance comparable with commercial solutions.
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Affiliation(s)
- Federico Mereu
- Centro Protesi Inail, Vigorso di Budrio, 40054 Bologna, Italy;
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
| | - Francesca Cordella
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
| | - Roberto Paolini
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
| | - Alessia Scarpelli
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
| | - Andrea Demofonti
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
| | - Loredana Zollo
- Unit of Advanced Robotics and Human-Centred Technologies, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.C.); (R.P.); (A.S.); (A.D.); (L.Z.)
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5
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Wang L, Liu S, Zhao W, Li J, Zeng H, Kang S, Sheng X, Wang L, Fan Y, Yin L. Recent Advances in Implantable Neural Interfaces for Multimodal Electrical Neuromodulation. Adv Healthc Mater 2024:e2303316. [PMID: 38323711 DOI: 10.1002/adhm.202303316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/29/2024] [Indexed: 02/08/2024]
Abstract
Electrical neuromodulation plays a pivotal role in enhancing patient outcomes among individuals suffering from neurological disorders. Implantable neural interfaces are vital components of the electrical neuromodulation system to ensure desirable performance; However, conventional devices are limited to a single function and are constructed with bulky and rigid materials, which often leads to mechanical incompatibility with soft tissue and an inability to adapt to the dynamic and complex 3D structures of biological systems. In addition, current implantable neural interfaces utilized in clinical settings primarily rely on wire-based techniques, which are associated with complications such as increased risk of infection, limited positioning options, and movement restrictions. Here, the state-of-art applications of electrical neuromodulation are presented. Material schemes and device structures that can be employed to develop robust and multifunctional neural interfaces, including flexibility, stretchability, biodegradability, self-healing, self-rolling, or morphing are discussed. Furthermore, multimodal wireless neuromodulation techniques, including optoelectronics, mechano-electrics, magnetoelectrics, inductive coupling, and electrochemically based self-powered devices are reviewed. In the end, future perspectives are given.
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Affiliation(s)
- Liu Wang
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Shengnan Liu
- School of Materials Science and Engineering, The Key Laboratory of Advanced Materials of Ministry of Education, State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Wentai Zhao
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Jiakun Li
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Haoxuan Zeng
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Shaoyang Kang
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Xing Sheng
- Department of Electronic Engineering, Beijing National Research Center for Information Science and Technology, Institute for Precision Medicine, Laboratory of Flexible Electronics Technology, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, 100084, China
| | - Lizhen Wang
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Yubo Fan
- Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, and with the School of Engineering Medicine, Beihang University, Beijing, 100083, P. R. China
| | - Lan Yin
- School of Materials Science and Engineering, The Key Laboratory of Advanced Materials of Ministry of Education, State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
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6
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Miziev S, Pawlak WA, Howard N. Comparative analysis of energy transfer mechanisms for neural implants. Front Neurosci 2024; 17:1320441. [PMID: 38292898 PMCID: PMC10825050 DOI: 10.3389/fnins.2023.1320441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/19/2023] [Indexed: 02/01/2024] Open
Abstract
As neural implant technologies advance rapidly, a nuanced understanding of their powering mechanisms becomes indispensable, especially given the long-term biocompatibility risks like oxidative stress and inflammation, which can be aggravated by recurrent surgeries, including battery replacements. This review delves into a comprehensive analysis, starting with biocompatibility considerations for both energy storage units and transfer methods. The review focuses on four main mechanisms for powering neural implants: Electromagnetic, Acoustic, Optical, and Direct Connection to the Body. Among these, Electromagnetic Methods include techniques such as Near-Field Communication (RF). Acoustic methods using high-frequency ultrasound offer advantages in power transmission efficiency and multi-node interrogation capabilities. Optical methods, although still in early development, show promising energy transmission efficiencies using Near-Infrared (NIR) light while avoiding electromagnetic interference. Direct connections, while efficient, pose substantial safety risks, including infection and micromotion disturbances within neural tissue. The review employs key metrics such as specific absorption rate (SAR) and energy transfer efficiency for a nuanced evaluation of these methods. It also discusses recent innovations like the Sectored-Multi Ring Ultrasonic Transducer (S-MRUT), Stentrode, and Neural Dust. Ultimately, this review aims to help researchers, clinicians, and engineers better understand the challenges of and potentially create new solutions for powering neural implants.
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7
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Marques-Almeida T, Lanceros-Mendez S, Ribeiro C. State of the Art and Current Challenges on Electroactive Biomaterials and Strategies for Neural Tissue Regeneration. Adv Healthc Mater 2024; 13:e2301494. [PMID: 37843074 DOI: 10.1002/adhm.202301494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/22/2023] [Indexed: 10/17/2023]
Abstract
The loss or failure of an organ/tissue stands as one of the healthcare system's most prevalent, devastating, and costly challenges. Strategies for neural tissue repair and regeneration have received significant attention due to their particularly strong impact on patients' well-being. Many research efforts are dedicated not only to control the disease symptoms but also to find solutions to repair the damaged tissues. Neural tissue engineering (TE) plays a key role in addressing this problem and significant efforts are being carried out to develop strategies for neural repair treatment. In the last years, active materials allowing to tune cell-materials interaction are being increasingly used, representing a recent paradigm in TE applications. Among the most important stimuli influencing cell behavior are the electrical and mechanical ones. In this way, materials with the ability to provide this kind of stimuli to the neural cells seem to be appropriate to support neural TE. In this scope, this review summarizes the different biomaterials types used for neural TE, highlighting the relevance of using active biomaterials and electrical stimulation. Furthermore, this review provides not only a compilation of the most relevant studies and results but also strategies for novel and more biomimetic approaches for neural TE.
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Affiliation(s)
- Teresa Marques-Almeida
- Physics Centre of Minho and Porto Universities (CF-UM-UP), University of Minho, Braga, 4710-057, Portugal
- LaPMET - Laboratory of Physics for Materials and Emergent Technologies, University of Minho, Braga, 4710-057, Portugal
| | - Senentxu Lanceros-Mendez
- Physics Centre of Minho and Porto Universities (CF-UM-UP), University of Minho, Braga, 4710-057, Portugal
- LaPMET - Laboratory of Physics for Materials and Emergent Technologies, University of Minho, Braga, 4710-057, Portugal
- BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV/EHU Science Park, Leioa, 48940, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, 48009, Spain
| | - Clarisse Ribeiro
- Physics Centre of Minho and Porto Universities (CF-UM-UP), University of Minho, Braga, 4710-057, Portugal
- LaPMET - Laboratory of Physics for Materials and Emergent Technologies, University of Minho, Braga, 4710-057, Portugal
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8
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Nair V, Dalrymple AN, Yu Z, Balakrishnan G, Bettinger CJ, Weber DJ, Yang K, Robinson JT. Miniature battery-free bioelectronics. Science 2023; 382:eabn4732. [PMID: 37943926 DOI: 10.1126/science.abn4732] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 09/28/2023] [Indexed: 11/12/2023]
Abstract
Miniature wireless bioelectronic implants that can operate for extended periods of time can transform how we treat disorders by acting rapidly on precise nerves and organs in a way that drugs cannot. To reach this goal, materials and methods are needed to wirelessly transfer energy through the body or harvest energy from the body itself. We review some of the capabilities of emerging energy transfer methods to identify the performance envelope for existing technology and discover where opportunities lie to improve how much-and how efficiently-we can deliver energy to the tiny bioelectronic implants that can support emerging medical technologies.
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Affiliation(s)
- Vishnu Nair
- Rice Neuroengineering Initiative, Rice University, Houston, TX, USA
| | - Ashley N Dalrymple
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Department of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, UT, USA
| | - Zhanghao Yu
- Department of Electrical and Computer Engineering, Rice University, Houston, TX, USA
| | - Gaurav Balakrishnan
- Department of Materials Science & Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Christopher J Bettinger
- Department of Materials Science & Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Douglas J Weber
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Center for Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Kaiyuan Yang
- Department of Electrical and Computer Engineering, Rice University, Houston, TX, USA
| | - Jacob T Robinson
- Rice Neuroengineering Initiative, Rice University, Houston, TX, USA
- Department of Electrical and Computer Engineering, Rice University, Houston, TX, USA
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9
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Hall TAG, Theodoridis K, Kechagias S, Kohli N, Denonville C, Rørvik PM, Cegla F, van Arkel RJ. Electromechanical and biological evaluations of 0.94Bi 0.5Na 0.5TiO 3-0.06BaTiO 3 as a lead-free piezoceramic for implantable bioelectronics. BIOMATERIALS ADVANCES 2023; 154:213590. [PMID: 37598437 DOI: 10.1016/j.bioadv.2023.213590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 08/01/2023] [Accepted: 08/13/2023] [Indexed: 08/22/2023]
Abstract
Smart implantable electronic medical devices are being developed to deliver healthcare that is more connected, personalised, and precise. Many of these implantables rely on piezoceramics for sensing, communication, energy autonomy, and biological stimulation, but the piezoceramics with the strongest piezoelectric coefficients are almost exclusively lead-based. In this article, we evaluate the electromechanical and biological characteristics of a lead-free alternative, 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (BNT-6BT), manufactured via two synthesis routes: the conventional solid-state method (PIC700) and tape casting (TC-BNT-6BT). The BNT-6BT materials exhibited soft piezoelectric properties, with d33 piezoelectric coefficients that were inferior to commonly used PZT (PIC700: 116 pC/N; TC-BNT-6BT: 121 pC/N; PZT-5A: 400 pC/N). The material may be viable as a lead-free substitute for soft PZT where moderate performance losses up to 10 dB are tolerable, such as pressure sensing and pulse-echo measurement. No short-term harmful biological effects of BNT-6BT were detected and the material was conducive to the proliferation of MC3T3-E1 murine preosteoblasts. BNT-6BT could therefore be a viable material for electroactive implants and implantable electronics without the need for hermetic sealing.
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Affiliation(s)
- Thomas A G Hall
- Biomechanics Group, Department of Mechanical Engineering, Imperial College London, UK
| | | | - Stylianos Kechagias
- Biomechanics Group, Department of Mechanical Engineering, Imperial College London, UK
| | - Nupur Kohli
- Biomechanics Group, Department of Mechanical Engineering, Imperial College London, UK; Biomedical Engineering Department, Khalifa University, United Arab Emirates
| | - Christelle Denonville
- Thin Film and Membrane Technology, Sustainable Energy Technology, SINTEF Industry, Norway
| | - Per Martin Rørvik
- Thin Film and Membrane Technology, Sustainable Energy Technology, SINTEF Industry, Norway
| | - Frederic Cegla
- Non-Destructive Evaluation Group, Department of Mechanical Engineering, Imperial College London, UK
| | - Richard J van Arkel
- Biomechanics Group, Department of Mechanical Engineering, Imperial College London, UK.
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10
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Su K, Qiu Z, Xu J. A 14-Bit, 12 V-to-100 V Voltage Compliance Electrical Stimulator with Redundant Digital Calibration. MICROMACHINES 2023; 14:2001. [PMID: 38004858 PMCID: PMC10672756 DOI: 10.3390/mi14112001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/26/2023]
Abstract
Electrical stimulation is an important technique for modulating the functions of the nervous system through electrical stimulus. To implement a more competitive prototype that can tackle the domain-specific difficulties of existing electrical stimulators, three key techniques are proposed in this work. Firstly, a load-adaptive power saving technique called over-voltage detection is implemented to automatically adjust the supply voltage. Secondly, redundant digital calibration (RDC) is proposed to improve current accuracy and ensure safety during long-term electrical stimulation without costing too much circuit area and power. Thirdly, a flexible waveform generator is designed to provide arbitrary stimulus waveforms for particular applications. Measurement results show the stimulator can adjust the supply voltage from 12 V to 100 V automatically, and the measured effective resolution of the stimulation current reaches 14 bits in a full range of 6.5 mA. Without applying charge balancing techniques, the average mismatch between the cathodic and anodic current pulses in biphasic stimulus is 0.0427%. The proposed electrical stimulator can generate arbitrary stimulus waveforms, including sine, triangle, rectangle, etc., and it is supposed to be competitive for implantable and wearable devices.
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Affiliation(s)
- Kangyu Su
- College of Information and Electronics Engineering, Zhejiang University, Hangzhou 310027, China; (K.S.); (Z.Q.)
- MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, Hangzhou 310058, China
| | - Zhang Qiu
- College of Information and Electronics Engineering, Zhejiang University, Hangzhou 310027, China; (K.S.); (Z.Q.)
- MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, Hangzhou 310058, China
| | - Jian Xu
- MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, Hangzhou 310058, China
- Nanhu Brain-Computer Interface Institute, Hangzhou 311100, China
- Affiliated Mental Health Center & Hangzhou Seventh People’s Hospital, Zhejiang University School of Medicine, Hangzhou 310013, China
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11
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Xu S, Momin M, Ahmed S, Hossain A, Veeramuthu L, Pandiyan A, Kuo CC, Zhou T. Illuminating the Brain: Advances and Perspectives in Optoelectronics for Neural Activity Monitoring and Modulation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2303267. [PMID: 37726261 DOI: 10.1002/adma.202303267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/30/2023] [Indexed: 09/21/2023]
Abstract
Optogenetic modulation of brain neural activity that combines optical and electrical modes in a unitary neural system has recently gained robust momentum. Controlling illumination spatial coverage, designing light-activated modulators, and developing wireless light delivery and data transmission are crucial for maximizing the use of optical neuromodulation. To this end, biocompatible electrodes with enhanced optoelectrical performance, device integration for multiplexed addressing, wireless transmission, and multimodal operation in soft systems have been developed. This review provides an outlook for uniformly illuminating large brain areas while spatiotemporally imaging the neural responses upon optoelectrical stimulation with little artifacts. Representative concepts and important breakthroughs, such as head-mounted illumination, multiple implanted optical fibers, and micro-light-delivery devices, are discussed. Examples of techniques that incorporate electrophysiological monitoring and optoelectrical stimulation are presented. Challenges and perspectives are posed for further research efforts toward high-density optoelectrical neural interface modulation, with the potential for nonpharmacological neurological disease treatments and wireless optoelectrical stimulation.
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Affiliation(s)
- Shumao Xu
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Marzia Momin
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Salahuddin Ahmed
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Arafat Hossain
- Department of Electrical Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
| | - Loganathan Veeramuthu
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Archana Pandiyan
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Chi-Ching Kuo
- Department of Molecular Science and Engineering, National Taipei University of Technology, Taipei, 10608, Republic of China
| | - Tao Zhou
- Department of Engineering Science and Mechanics, Center for Neural Engineering, The Pennsylvania State University, Pennsylvania, 16802, USA
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12
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Sanchez-Rojas JL. Editorial for the Special Issue on Piezoelectric Transducers: Materials, Devices and Applications, Volume III. MICROMACHINES 2023; 14:1862. [PMID: 37893299 PMCID: PMC10609083 DOI: 10.3390/mi14101862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/29/2023]
Abstract
This is the third volume of a Special Issue focused on piezoelectric transducers, covering a wide range of topics, including the design, fabrication, characterization, packaging and system integration or final applications of mili/micro/nano-electro-mechanical system-based transducers featuring piezoelectric materials and devices [...].
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Affiliation(s)
- Jose Luis Sanchez-Rojas
- Microsystems, Actuators and Sensors Lab, Institute of Nanotechnology, Universidad de Castilla-La Mancha, 45071 Toledo, Spain
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13
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Kim W, Tuppen CA, Alrashdan F, Singer A, Weirnick R, Robinson JT. Magnetoelectrics enables large power delivery to mm-sized wireless bioelectronics. JOURNAL OF APPLIED PHYSICS 2023; 134:094103. [PMID: 37692260 PMCID: PMC10484622 DOI: 10.1063/5.0156015] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/17/2023] [Indexed: 09/12/2023]
Abstract
To maximize the capabilities of minimally invasive implantable bioelectronic devices, we must deliver large amounts of power to small implants; however, as devices are made smaller, it becomes more difficult to transfer large amounts of power without a wired connection. Indeed, recent work has explored creative wireless power transfer (WPT) approaches to maximize power density [the amount of power transferred divided by receiver footprint area (length × width)]. Here, we analyzed a model for WPT using magnetoelectric (ME) materials that convert an alternating magnetic field into an alternating voltage. With this model, we identify the parameters that impact WPT efficiency and optimize the power density. We find that improvements in adhesion between the laminated ME layers, clamping, and selection of material thicknesses lead to a power density of 3.1 mW/mm2, which is over four times larger than previously reported for mm-sized wireless bioelectronic implants at a depth of 1 cm or more in tissue. This improved power density allows us to deliver 31 and 56 mW to 10 and 27-mm2 ME receivers, respectively. This total power delivery is over five times larger than similarly sized bioelectronic devices powered by radiofrequency electromagnetic waves, inductive coupling, ultrasound, light, capacitive coupling, or previously reported magnetoelectrics. This increased power density opens the door to more power-intensive bioelectronic applications that have previously been inaccessible using mm-sized battery-free devices.
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Affiliation(s)
- Wonjune Kim
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - C. Anne Tuppen
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Fatima Alrashdan
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Amanda Singer
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Rachel Weirnick
- Pratt School of Engineering, Duke University, Durham, North Carolina 27708, USA
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14
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Kim W, Tuppen CA, Alrashdan F, Singer A, Weirnick R, Robinson JT. Magnetoelectrics Enables Large Power Delivery to mm-Sized Wireless Bioelectronics. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.01.555944. [PMID: 37732216 PMCID: PMC10508743 DOI: 10.1101/2023.09.01.555944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
To maximize the capabilities of minimally invasive implantable bioelectronic devices, we must deliver large amounts of power to small implants; however, as devices are made smaller, it becomes more difficult to transfer large amounts of power without a wired connection. Indeed, recent work has explored creative wireless power transfer (WPT) approaches to maximize power density (the amount of power transferred divided by receiver footprint area (length × width)). Here, we analyzed a model for WPT using magnetoelectric (ME) materials that convert an alternating magnetic field into an alternating voltage. With this model, we identify the parameters that impact WPT efficiency and optimize the power density. We find that improvements in adhesion between the laminated ME layers, clamping, and selection of material thicknesses lead to a power density of 3.1 mW/mm 2 , which is over 4 times larger than previously reported for mm-sized wireless bioelectronic implants at a depth of 1 cm or more in tissue. This improved power density allows us to deliver 31 mW and 56 mW to 10-mm 2 and 27-mm 2 ME receivers, respectively. This total power delivery is over 5 times larger than similarly sized bioelectronic devices powered by radiofrequency electromagnetic waves, inductive coupling, ultrasound, light, capacitive coupling, or previously reported magnetoelectrics. This increased power density opens the door to more power-intensive bioelectronic applications that have previously been inaccessible using mm-sized battery-free devices.
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15
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Kashani Z, Kiani M. A Study on Ultrasonic Wireless Power Transfer With Phased Array for Biomedical Implants. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2023; 17:713-724. [PMID: 37267144 PMCID: PMC10664043 DOI: 10.1109/tbcas.2023.3282197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This article presents the design, fabrication, and sensitivity analysis of an ultrasound (US) wireless power transfer (WPT) link using an external phased array. Optimal beam focusing and steering is needed for efficient, safe, and reliable US WPT to biomedical implants with millimeter (mm) dimensions. Therefore, the main contributions of this work include the investigation of the 1) performance of the US WPT link using different mm-sized US receivers, 2) effect of different types of errors in the delay profile of the beamforming system on the delivered power, and 3) implant's localization. In measurements, the fabricated 0.94 MHz, 32-element array (39.48 × 9.6 × 2 mm3) driven by 25 V pulses with beam focusing and steering capability up to 50 mm depth and ±60o angle could deliver power to different mm-sized US receivers within the FDA safety limit of 720 mW/cm2. Specifically, several US transducers with a 1 mm dimension (sphere, cubic, disc shape) and 2 mm dimension (disc shape) received 0.095 mW, 0.25 mW, 0.22 mW, and 0.53 mW, respectively, at a 30 mm depth (0o steering angle). Among these transducers, the sphere shape transducer featured less sensitivity to misalignments. A random error in the phased array delays had a more drastic effect on delivered power reduction. For implant's localization, the measurement results demonstrated comparable power delivery by measuring pulse delays of only 5 elements (out of 32 elements) using 4 different interpolation methods.
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16
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Habibagahi I, Jang J, Babakhani A. Miniaturized Wirelessly Powered and Controlled Implants for Multisite Stimulation. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES 2023; 71:1911-1922. [PMID: 38645708 PMCID: PMC11031205 DOI: 10.1109/tmtt.2022.3233368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
This paper presents a miniaturized implant with a diameter of only 14 mm, which houses a novel System on Chip (SoC) enabling two voltage level stimulation of up to 16 implants using a single Tx coil. Each implant can operate at a distance of 80 mm in the air through the inductive resonant link. The SoC consumes only 27 μW static power and enables two channels with stimulation amplitudes of 1.8 V and 3.3 V and timing resolution of 100 μs. The SoC is implemented in the standard 180 nm complementary metal oxide semiconductor (CMOS) technology and has an area of 0.75 mm × 1.6 mm. The SoC comprises an RF rectifier, low drop-out regulator (LDO), error detection block, clock data recovery, finite state machine (FSM), and output stage. Each implant has a PCB-defined passcode, which enables the individual addressability of the implants for synchronized therapies. The implantable device weighs only 80 mg and sizes 20.1 mm3. Tolerance of up to 70° to angular misalignment was measured at a distance of 50 mm. The efficacy of bilateral stimulation was further verified by implanting two devices on two sides of a pig's neck and performing bilateral vagus nerve stimulation (VNS), while monitoring the heart rate.
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Affiliation(s)
- Iman Habibagahi
- Department of Electrical Engineering, University of California, Los Angeles, CA 90095 USA
| | - Jaeeun Jang
- Department of Electrical Engineering, University of California, Los Angeles, CA 90095 USA
| | - Aydin Babakhani
- Department of Electrical Engineering, University of California, Los Angeles, CA 90095 USA
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17
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Shen K, Chen O, Edmunds JL, Piech DK, Maharbiz MM. Translational opportunities and challenges of invasive electrodes for neural interfaces. Nat Biomed Eng 2023; 7:424-442. [PMID: 37081142 DOI: 10.1038/s41551-023-01021-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 02/15/2023] [Indexed: 04/22/2023]
Abstract
Invasive brain-machine interfaces can restore motor, sensory and cognitive functions. However, their clinical adoption has been hindered by the surgical risk of implantation and by suboptimal long-term reliability. In this Review, we highlight the opportunities and challenges of invasive technology for clinically relevant electrophysiology. Specifically, we discuss the characteristics of neural probes that are most likely to facilitate the clinical translation of invasive neural interfaces, describe the neural signals that can be acquired or produced by intracranial electrodes, the abiotic and biotic factors that contribute to their failure, and emerging neural-interface architectures.
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Affiliation(s)
- Konlin Shen
- University of California, Berkeley - University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA.
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA.
| | - Oliver Chen
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, USA
| | - Jordan L Edmunds
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, USA
| | - David K Piech
- University of California, Berkeley - University of California, San Francisco Graduate Program in Bioengineering, Berkeley, CA, USA
| | - Michel M Maharbiz
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, CA, USA
- Department of Bioengineering, University of California, Berkeley, CA, USA
- Chan-Zuckerberg Biohub, San Francisco, CA, USA
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18
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Liu G, Lv Z, Batool S, Li MZ, Zhao P, Guo L, Wang Y, Zhou Y, Han ST. Biocompatible Material-Based Flexible Biosensors: From Materials Design to Wearable/Implantable Devices and Integrated Sensing Systems. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2207879. [PMID: 37009995 DOI: 10.1002/smll.202207879] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/28/2023] [Indexed: 06/19/2023]
Abstract
Human beings have a greater need to pursue life and manage personal or family health in the context of the rapid growth of artificial intelligence, big data, the Internet of Things, and 5G/6G technologies. The application of micro biosensing devices is crucial in connecting technology and personalized medicine. Here, the progress and current status from biocompatible inorganic materials to organic materials and composites are reviewed and the material-to-device processing is described. Next, the operating principles of pressure, chemical, optical, and temperature sensors are dissected and the application of these flexible biosensors in wearable/implantable devices is discussed. Different biosensing systems acting in vivo and in vitro, including signal communication and energy supply are then illustrated. The potential of in-sensor computing for applications in sensing systems is also discussed. Finally, some essential needs for commercial translation are highlighted and future opportunities for flexible biosensors are considered.
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Affiliation(s)
- Gang Liu
- Institute of Microscale Optoelectronics and College of Electronics and Information Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Ziyu Lv
- Institute of Microscale Optoelectronics and College of Electronics and Information Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Saima Batool
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, P. R. China
| | | | - Pengfei Zhao
- Institute of Microscale Optoelectronics and College of Electronics and Information Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Liangchao Guo
- College of Mechanical Engineering, Yangzhou University, Yangzhou, 225127, P. R. China
| | - Yan Wang
- School of Microelectronics, Hefei University of Technology, Hefei, 230009, P. R. China
| | - Ye Zhou
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Su-Ting Han
- Institute of Microscale Optoelectronics and College of Electronics and Information Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
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19
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Kim HJ, Sritandi W, Xiong Z, Ho JS. Bioelectronic devices for light-based diagnostics and therapies. BIOPHYSICS REVIEWS 2023; 4:011304. [PMID: 38505817 PMCID: PMC10903427 DOI: 10.1063/5.0102811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 12/28/2022] [Indexed: 03/21/2024]
Abstract
Light has broad applications in medicine as a tool for diagnosis and therapy. Recent advances in optical technology and bioelectronics have opened opportunities for wearable, ingestible, and implantable devices that use light to continuously monitor health and precisely treat diseases. In this review, we discuss recent progress in the development and application of light-based bioelectronic devices. We summarize the key features of the technologies underlying these devices, including light sources, light detectors, energy storage and harvesting, and wireless power and communications. We investigate the current state of bioelectronic devices for the continuous measurement of health and on-demand delivery of therapy. Finally, we highlight major challenges and opportunities associated with light-based bioelectronic devices and discuss their promise for enabling digital forms of health care.
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Affiliation(s)
| | - Weni Sritandi
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore
| | | | - John S. Ho
- Author to whom correspondence should be addressed:
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20
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Sood A, Desseigne M, Dev A, Maurizi L, Kumar A, Millot N, Han SS. A Comprehensive Review on Barium Titanate Nanoparticles as a Persuasive Piezoelectric Material for Biomedical Applications: Prospects and Challenges. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2206401. [PMID: 36585372 DOI: 10.1002/smll.202206401] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Stimulation of cells with electrical cues is an imperative approach to interact with biological systems and has been exploited in clinical practices over a wide range of pathological ailments. This bioelectric interface has been extensively explored with the help of piezoelectric materials, leading to remarkable advancement in the past two decades. Among other members of this fraternity, colloidal perovskite barium titanate (BaTiO3 ) has gained substantial interest due to its noteworthy properties which includes high dielectric constant and excellent ferroelectric properties along with acceptable biocompatibility. Significant progression is witnessed for BaTiO3 nanoparticles (BaTiO3 NPs) as potent candidates for biomedical applications and in wearable bioelectronics, making them a promising personal healthcare platform. The current review highlights the nanostructured piezoelectric bio interface of BaTiO3 NPs in applications comprising drug delivery, tissue engineering, bioimaging, bioelectronics, and wearable devices. Particular attention has been dedicated toward the fabrication routes of BaTiO3 NPs along with different approaches for its surface modifications. This review offers a comprehensive discussion on the utility of BaTiO3 NPs as active devices rather than passive structural unit behaving as carriers for biomolecules. The employment of BaTiO3 NPs presents new scenarios and opportunity in the vast field of nanomedicines for biomedical applications.
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Affiliation(s)
- Ankur Sood
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
| | - Margaux Desseigne
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Atul Dev
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of California Davis, 2921 Stockton Boulevard, Sacramento, CA, 95817, USA
| | - Lionel Maurizi
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Anuj Kumar
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
- Institute of Cell Culture, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
| | - Nadine Millot
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS/Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47870, Dijon, 21078, France
| | - Sung Soo Han
- School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
- Institute of Cell Culture, Yeungnam University, 280 Daehak-ro, Gyeongsan, 38541, South Korea
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21
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Systematic investigation of self-image-guided ultrasonic transceiver using time interval measurements for wireless power transfer. Biomed Signal Process Control 2023. [DOI: 10.1016/j.bspc.2022.104482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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22
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Khalifa A, Nasrollahpour M, Nezaratizadeh A, Sha X, Stanaćević M, Sun NX, Cash SS. Fabrication and Assembly Techniques for Sub-mm Battery-Free Epicortical Implants. MICROMACHINES 2023; 14:476. [PMID: 36838175 PMCID: PMC9966084 DOI: 10.3390/mi14020476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/11/2023] [Accepted: 02/16/2023] [Indexed: 06/18/2023]
Abstract
Over the past three decades, we have seen significant advances in the field of wireless implantable medical devices (IMDs) that can interact with the nervous system. To further improve the stability, safety, and distribution of these interfaces, a new class of implantable devices is being developed: single-channel, sub-mm scale, and wireless microelectronic devices. In this research, we describe a new and simple technique for fabricating and assembling a sub-mm, wirelessly powered stimulating implant. The implant consists of an ASIC measuring 900 × 450 × 80 µm3, two PEDOT-coated microelectrodes, an SMD inductor, and a SU-8 coating. The microelectrodes and SMD are directly mounted onto the ASIC. The ultra-small device is powered using electromagnetic (EM) waves in the near-field using a two-coil inductive link and demonstrates a maximum achievable power transfer efficiency (PTE) of 0.17% in the air with a coil separation of 0.5 cm. In vivo experiments conducted on an anesthetized rat verified the efficiency of stimulation.
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Affiliation(s)
- Adam Khalifa
- Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Mehdi Nasrollahpour
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA
| | - Ali Nezaratizadeh
- Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Xiao Sha
- Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Milutin Stanaćević
- Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Nian X. Sun
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA
| | - Sydney S. Cash
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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23
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Benbuk A, Esmaeili H, Liu S, Patino-Guerrero A, Migrino RQ, Chae J, Nikkhah M, Blain Christen J. Passive and Flexible Wireless Electronics Fabricated on Parylene/PDMS Substrate for Stimulation of Human Stem Cell-Derived Cardiomyocytes. ACS Sens 2022; 7:3287-3297. [PMID: 36281962 PMCID: PMC9706816 DOI: 10.1021/acssensors.2c00794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In this paper, we report the development of a wireless, passive, biocompatible, and flexible system for stimulation of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMS). Fabricated on a transparent parylene/PDMS substrate, the proposed stimulator enables real-time excitation and characterization of hiPSC-CMs cultured on-board. The device comprises a rectenna operating at 2.35 GHz which receives radio frequency (RF) energy from an external transmitter and converts it into DC voltage to deliver monophasic stimulation. The operation of the stimulator was primarily verified by delivering monophasic voltage pulses through gold electrodes to hiPSC-CMs cultured on the Matrigel-coated substrates. Stimulated hiPSC-CMs beat in accordance with the monophasic pulses when delivered at 0.5, 1, and 2 Hz pulsing frequency, while no significant cell death was observed. The wireless stimulator could generate monophasic pulses with an amplitude of 8 V at a distance of 15 mm. These results demonstrated the proposed wireless stimulator's efficacy for providing electrical stimulation to engineered cardiac tissues. The proposed stimulator will have a wide application in tissue engineering where a fully wireless stimulation of electroconductive cells is needed. The device also has potential to be employed as a cardiac stimulator by delivering external stimulation and regulating the contractions of cardiac tissue.
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Affiliation(s)
- Ahmed
Abed Benbuk
- School of
Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706, United States
| | - Hamid Esmaeili
- School
of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona 85281, United States
| | - Shiyi Liu
- School of
Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706, United States
| | - Alejandra Patino-Guerrero
- School
of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona 85281, United States
| | - Raymond Q. Migrino
- Phoenix
Veterans Affairs Health Care System, Phoenix, Arizona 85022, United States,University
of Arizona College of Medicine, Phoenix, Arizona 85004, United States
| | - Junseok Chae
- School of
Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706, United States
| | - Mehdi Nikkhah
- School
of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona 85281, United States,Center
for Personalized Diagnostics (CPD), Biodesign Institute, Arizona State University, Tempe, Arizona 85287, United States,
| | - Jennifer Blain Christen
- School of
Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706, United States,
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24
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Zhao L, Annayev M, Oralkan O, Jia Y. An Ultrasonic Energy Harvesting IC Providing Adjustable Bias Voltage for Pre-Charged CMUT. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:842-851. [PMID: 35671313 DOI: 10.1109/tbcas.2022.3178581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Ultrasonic wireless power transmission (WPT) using pre-charged capacitive micromachined ultrasonic transducers (CMUT) is drawing great attention due to the easy integration of CMUT with CMOS techniques. Here, we present an integrated circuit (IC) that interfaces with a pre-charged CMUT device for ultrasonic energy harvesting. We implemented an adaptive high voltage charge pump (HVCP) in the proposed IC, which features low power, overvoltage stress (OVS) robustness, and a wide output range. The ultrasonic energy harvesting IC is fabricated in the 180 nm HV BCD process and occupies a 2 × 2.5 mm2 silicon area. The adaptive HVCP offers a 2× - 12× voltage conversion ratio (VCR), thereby providing a wide bias voltage range of 4 V-44 V for the pre-charged CMUT. Moreover, a VCR tunning finite state machine (FSM) implemented in the proposed IC can dynamically adjust the VCR to stabilize the HVCP output (i.e., the pre-charged CMUT bias voltage) to a target voltage in a closed-loop manner. Such a closed-loop control mechanism improves the tolerance of the proposed IC to the received power variation caused by misalignments, amount of transmitted power change, and/or load variation. Besides, the proposed ultrasonic energy harvesting IC has an average power consumption of 35 μW-554 μW corresponding to the HVCP output from 4 V-44 V. The CMUT device with a local surface acoustic intensity of 3.78 mW/mm2, which is well below the FDA limit for power flux (7.2 mW/mm2), can deliver sufficient power to the IC.
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25
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Benedict BC, Ghanbari MM, Muller R. Phased Array Beamforming Methods for Powering Biomedical Ultrasonic Implants. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:2756-2765. [PMID: 35939455 DOI: 10.1109/tuffc.2022.3197705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Millimeter-scale implants using ultrasound (US) for power and communication have been proposed for a range of deep-tissue applications, including neural recording and stimulation. However, published implementations have shown high sensitivity to misalignment with the external US transducer. Ultrasonic beamforming using a phased array to these implants can improve tolerance to misalignment, reduce implant volume, and allow multiple implants to be operated simultaneously in different locations. This article details the design of a custom planar phased array US system, which is capable of steering and focusing US power within a 3-D volume. Analysis and simulation is performed to determine the choice of array element pitch, with special attention given to maximizing the power available at the implant while meeting FDA limits for diagnostic US. Time reversal (TR) is proposed as a computationally simple approach to beamforming that is robust despite scattering and inhomogeneity of the acoustic medium. This technique is demonstrated both in active drive and pulse-echo modes, and it is experimentally compared with other beamforming techniques by measuring energy transfer efficiency. Simultaneous power delivery to multiple implants is also demonstrated.
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26
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Liu F, Wu Y, Almarri N, Habibollahi M, Lancashire HT, Bryson B, Greensmith L, Jiang D, Demosthenous A. A Fully Implantable Opto-Electro Closed-Loop Neural Interface for Motor Neuron Disease Studies. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:752-765. [PMID: 36018872 DOI: 10.1109/tbcas.2022.3202026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This paper presents a fully implantable closed-loop device for use in freely moving rodents to investigate new treatments for motor neuron disease. The 0.18 μm CMOS integrated circuit comprises 4 stimulators, each featuring 16 channels for optical and electrical stimulation using arbitrary current waveforms at frequencies from 1.5 Hz to 50 kHz, and a bandwidth programmable front-end for neural recording. The implant uses a Qi wireless inductive link which can deliver >100 mW power at a maximum distance of 2 cm for a freely moving rodent. A backup rechargeable battery can support 10 mA continuous stimulation currents for 2.5 hours in the absence of an inductive power link. The implant is controlled by a graphic user interface with broad programmable parameters via a Bluetooth low energy bidirectional data telemetry link. The encapsulated implant is 40 mm × 20 mm × 10 mm. Measured results are presented showing the electrical performance of the electronics and the packaging method.
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27
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Valente V. Evolution of Biotelemetry in Medical Devices: From Radio Pills to mm-Scale Implants. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:580-599. [PMID: 35834463 DOI: 10.1109/tbcas.2022.3190767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The advent of semiconductor technology in the mid-20th century created unprecedented opportunities to develop a new generation of small-scale wireless medical sensing devices that can support remote monitoring of patients' vital signs. The first radio pills were developed as early as the 1950's using only a few transistors. These swallowable capsules could sense and wirelessly transmit vital parameters from inside the human body. Since then we have witnessed the rapid progress of medical devices driven by the evolution of semiconductor technology, from single-transistor oscillators to complex mixed-signal multi-channel and multi-modal systems. This paper retraces the evolution of biotelemetry devices from their very early inception to the smart miniaturized systems of modern days, focusing on semiconductor-enabled sensing methods and circuits developed over the last six decades. The paper also includes the author's perspective on current and future trends in the development of CMOS-based biotelemeters, focusing on concepts of implant modularity, miniaturization and hybrid energy harvesting solutions.
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28
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Kim HJ, Ho JS. Wireless interfaces for brain neurotechnologies. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2022; 380:20210020. [PMID: 35658679 DOI: 10.1098/rsta.2021.0020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 12/13/2021] [Indexed: 06/15/2023]
Abstract
Wireless interfaces enable brain-implanted devices to remotely interact with the external world. They are critical components in modern research and clinical neurotechnologies and play a central role in determining their overall size, lifetime and functionality. Wireless interfaces use a wide range of modalities-including radio-frequency fields, acoustic waves and light-to transfer energy and data to and from an implanted device. These forms of energy interact with living tissue through distinct mechanisms and therefore lead to systems with vastly different form factors, operating characteristics, and safety considerations. This paper reviews recent advances in the development of wireless interfaces for brain neurotechnologies. We summarize the requirements that state-of-the-art brain-implanted devices impose on the wireless interface, and discuss the working principles and applications of wireless interfaces based on each modality. We also investigate challenges associated with wireless brain neurotechnologies and discuss emerging solutions permitted by recent developments in electrical engineering and materials science. This article is part of the theme issue 'Advanced neurotechnologies: translating innovation for health and well-being'.
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Affiliation(s)
- Han-Joon Kim
- Department of Electrical and Computer Engineering National University of Singapore, Queenstown, Singapore
| | - John S Ho
- Department of Electrical and Computer Engineering National University of Singapore, Queenstown, Singapore
- The N.1 Institute for Health National University of Singapore, Queenstown, Singapore
- Institute for Health Innovation and Technology, National University of Singapore, Queenstown, Singapore
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Physical Stimulation Combined with Biomaterials Promotes Peripheral Nerve Injury Repair. Bioengineering (Basel) 2022; 9:bioengineering9070292. [PMID: 35877343 PMCID: PMC9311987 DOI: 10.3390/bioengineering9070292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/11/2022] [Accepted: 06/13/2022] [Indexed: 11/17/2022] Open
Abstract
Peripheral nerve injury (PNI) is a clinical problem with high morbidity that can cause severe damage. Surgical suturing or implants are usually required due to the slow speed and numerous factors affecting repair after PNI. An autologous nerve graft is the gold standard for PNI repair among implants. However, there is a potential problem of the functional loss of the donor site. Therefore, tissue-engineered nerve biomaterials are often used to bridge the gap between nerve defects, but the therapeutic effect is insufficient. In order to enhance the repair effect of nerve biomaterials for PNI, researchers are seeking to combine various stimulation elements, such as the addition of biological factors such as nerve growth factors or physical factors such as internal microstructural modifications of catheters and their combined application with physical stimulation therapy. Physical stimulation therapy is safer, is more convenient, and has more practical features than other additive factors. Its feasibility and convenience, when combined with nerve biomaterials, provide broader application prospects for PNI repair, and has therefore become a research hot spot. This paper will review the combined application of physical stimulation and biomaterials in PNI repair in recent years to provide new therapeutic ideas for the future use of physical stimulation in PNI repair.
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Zhang Y, Muthuraman P, Andino-Pavlovsky V, Uguz I, Elloian J, Shepard KL. Augmented ultrasonography with implanted CMOS electronic motes. Nat Commun 2022; 13:3521. [PMID: 35725979 PMCID: PMC9209459 DOI: 10.1038/s41467-022-31166-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 06/07/2022] [Indexed: 11/09/2022] Open
Abstract
Modern clinical practice benefits significantly from imaging technologies and much effort is directed toward making this imaging more informative through the addition of contrast agents or reporters. Here, we report the design of a battery-less integrated circuit mote acting as an electronic reporter during medical ultrasound imaging. When implanted within the field-of-view of a brightness-mode (B-mode) ultrasound imager, this mote transmits information from its location through backscattered acoustic energy which is captured within the ultrasound image itself. We prototype and characterize the operation of such motes in vitro and in vivo. Performing with a static power consumption of less than 57 pW, the motes operate at duty cycles for receiving acoustic energy as low as 50 ppm. Motes within the same field-of-view during imaging have demonstrated signal-to-noise ratios of more than 19.1 dB at depths of up to 40 mm in lossy phantom. Physiological information acquired through such motes, which is beyond what is measurable with endogenous ultrasound backscatter and which is biogeographically located within an image, has the potential to provide an augmented ultrasonography.
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Affiliation(s)
- Yihan Zhang
- Department of Electrical Engineering, Columbia University, New York, NY, 10027, USA.,School of Integrated Circuits, Peking University, Beijing, P. R. China
| | - Prashant Muthuraman
- Department of Electrical Engineering, Columbia University, New York, NY, 10027, USA
| | | | - Ilke Uguz
- Department of Electrical Engineering, Columbia University, New York, NY, 10027, USA
| | - Jeffrey Elloian
- Department of Electrical Engineering, Columbia University, New York, NY, 10027, USA
| | - Kenneth L Shepard
- Department of Electrical Engineering, Columbia University, New York, NY, 10027, USA.
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Zhu Y, Li S, Li J, Falcone N, Cui Q, Shah S, Hartel MC, Yu N, Young P, de Barros NR, Wu Z, Haghniaz R, Ermis M, Wang C, Kang H, Lee J, Karamikamkar S, Ahadian S, Jucaud V, Dokmeci MR, Kim HJ, Khademhosseini A. Lab-on-a-Contact Lens: Recent Advances and Future Opportunities in Diagnostics and Therapeutics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108389. [PMID: 35130584 PMCID: PMC9233032 DOI: 10.1002/adma.202108389] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 01/27/2022] [Indexed: 05/09/2023]
Abstract
The eye is one of the most complex organs in the human body, containing rich and critical physiological information (e.g., intraocular pressure, corneal temperature, and pH) as well as a library of metabolite biomarkers (e.g., glucose, proteins, and specific ions). Smart contact lenses (SCLs) can serve as a wearable intelligent ocular prosthetic device capable of noninvasive and continuous monitoring of various essential physical/biochemical parameters and drug loading/delivery for the treatment of ocular diseases. Advances in SCL technologies and the growing public interest in personalized health are accelerating SCL research more than ever before. Here, the current status and potential of SCL development through a comprehensive review from fabrication to applications to commercialization are discussed. First, the material, fabrication, and platform designs of the SCLs for the diagnostic and therapeutic applications are discussed. Then, the latest advances in diagnostic and therapeutic SCLs for clinical translation are reviewed. Later, the established techniques for wearable power transfer and wireless data transmission applied to current SCL devices are summarized. An outlook, future opportunities, and challenges for developing next-generation SCL devices are also provided. With the rise in interest of SCL development, this comprehensive and essential review can serve as a new paradigm for the SCL devices.
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Affiliation(s)
- Yangzhi Zhu
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Shaopei Li
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Jinghang Li
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
- School of Engineering, Westlake University, Hangzhou, Zhejiang Province, 310024, China
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei Province, 430205, China
| | - Natashya Falcone
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Qingyu Cui
- Department of Medicine, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Shilp Shah
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Martin C Hartel
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Ning Yu
- Department of Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA, 92521, USA
| | - Patric Young
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | | | - Zhuohong Wu
- Department of Nanoengineering, University of California-San Diego, San Diego, CA, 92093, USA
| | - Reihaneh Haghniaz
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Menekse Ermis
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Canran Wang
- Andrew and Peggy Cherng Department of Medical Engineering, Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Heemin Kang
- Department of Materials Science and Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Junmin Lee
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | | | - Samad Ahadian
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Vadim Jucaud
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Mehmet R Dokmeci
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Han-Jun Kim
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
| | - Ali Khademhosseini
- Terasaki Institute for Biomedical Innovation, Los Angeles, CA, 90064, USA
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Khan SR, Mugisha AJ, Tsiamis A, Mitra S. Commercial Off-the-Shelf Components (COTS) in Realizing Miniature Implantable Wireless Medical Devices: A Review. SENSORS 2022; 22:s22103635. [PMID: 35632042 PMCID: PMC9144583 DOI: 10.3390/s22103635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/25/2022] [Accepted: 04/30/2022] [Indexed: 12/04/2022]
Abstract
Over the past decade, there has been exponential growth in the per capita rate of medical patients around the world, and this is significantly straining the resources of healthcare institutes. Therefore, the reliance on smart commercial off-the-shelf (COTS) implantable wireless medical devices (IWMDs) is increasing among healthcare institutions to provide routine medical services, such as monitoring patients' physiological signals and the remote delivery of therapeutic drugs. These smart COTS IWMDs reduce the necessity of recurring visits of patients to healthcare institutions and also mitigate physical contact, which can minimize the possibility of any potential spread of contagious diseases. Furthermore, the devices provide patients with the benefit of recuperating in familiar surroundings. As such, low-cost, ubiquitous COTS IWMDs have engendered the proliferation of telemedicine in healthcare to provide routine medical services. In this paper, a review work on COTS IWMDs is presented at a macro level to discuss the history of IWMDs, different networked COTS IWMDs, health and safety regulations of COTS IWMDs and the importance of organized procurement. Furthermore, we discuss the basic building blocks of IWMDs and how COTS components can contribute to build these blocks over widely researched custom-built application-specific integrated circuits.
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Shah J, Quinkert C, Collar B, Williams M, Biggs E, Irazoqui P. A Highly Miniaturized, Chronically Implanted ASIC for Electrical Nerve Stimulation. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:233-243. [PMID: 35201991 PMCID: PMC9195150 DOI: 10.1109/tbcas.2022.3153282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We present a wireless, fully implantable device for electrical stimulation of peripheral nerves consisting of a powering coil, a tuning network, a Zener diode, selectable stimulation parameters, and a stimulator IC, all encapsulated in biocompatible silicone. A wireless RF signal at 13.56 MHz powers the implant through the on-chip rectifier. The ASIC, designed in TSMC's 180 nm MS RF G process, occupies an area of less than 1.2 mm2. The IC enables externally selectable current-controlled stimulation through an on-chip read-only memory with a wide range of 32 stimulation parameters (90-750 µA amplitude, 100 µs or 1 ms pulse width, 15 or 50 Hz frequency). The IC generates the constant current waveform using an 8-bit binary weighted DAC and an H-Bridge. At the most power-hungry stimulation parameter, the average power consumption during a stimulus pulse is 2.6 mW with a power transfer efficiency of ∼5.2%. In addition to benchtop and acute testing, we chronically implanted two versions of the device (a design with leads and a leadless design) on two rats' sciatic nerves to verify the long-term efficacy of the IC and the full system. The leadless device had the following dimensions: height of 0.45 cm, major axis of 1.85 cm, and minor axis of 1.34 cm, with similar dimensions for the device with leads. Both devices were implanted and worked for experiments lasting from 21-90 days. To the best of our knowledge, the fabricated IC is the smallest constant-current stimulator that has been tested chronically.
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Deng W, Zhou Y, Libanori A, Chen G, Yang W, Chen J. Piezoelectric nanogenerators for personalized healthcare. Chem Soc Rev 2022; 51:3380-3435. [PMID: 35352069 DOI: 10.1039/d1cs00858g] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The development of flexible piezoelectric nanogenerators has experienced rapid progress in the past decade and is serving as the technological foundation of future state-of-the-art personalized healthcare. Due to their highly efficient mechanical-to-electrical energy conversion, easy implementation, and self-powering nature, these devices permit a plethora of innovative healthcare applications in the space of active sensing, electrical stimulation therapy, as well as passive human biomechanical energy harvesting to third party power on-body devices. This article gives a comprehensive review of the piezoelectric nanogenerators for personalized healthcare. After a brief introduction to the fundamental physical science of the piezoelectric effect, material engineering strategies, device structural designs, and human-body centered energy harvesting, sensing, and therapeutics applications are also systematically discussed. In addition, the challenges and opportunities of utilizing piezoelectric nanogenerators for self-powered bioelectronics and personalized healthcare are outlined in detail.
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Affiliation(s)
- Weili Deng
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, USA. .,School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
| | - Yihao Zhou
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, USA.
| | - Alberto Libanori
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, USA.
| | - Guorui Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, USA.
| | - Weiqing Yang
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
| | - Jun Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, USA.
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A 28 nm Bulk CMOS Fully Digital BPSK Demodulator for US-Powered IMDs Downlink Communications. ELECTRONICS 2022. [DOI: 10.3390/electronics11050698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Low-invasive and battery-less implantable medical devices (IMDs) have been increasingly emerging in recent years. The developed solutions in the literature often concentrate on the Bidirectional Data-Link for long-term monitoring devices. Indeed, their ability to collect data and communicate them to the external world, namely Data Up-Link, has revealed a promising solution for bioelectronic medicine. Furthermore, the capacity to control organs such as the brain, nerves, heart-beat and gastrointestinal activities, made up through the manipulation of electrical transducers, could optimise therapeutic protocols and help patients’ pain relief. These kinds of stimulations come from the modulation of a powering signal generated from an externally placed unit coupled to the implanted receivers for power/data exchanging. The established communication is also defined as a Data Down-Link. In this framework, a new solution of the Binary Phase-Shift Keying (BPSK) demodulator is presented in this paper in order to design a robust, low-area, and low-power Down-Link for ultrasound (US)-powered IMDs. The implemented system is fully digital and PLL-free, thus reducing area occupation and making it fully synthesizable. Post-layout simulation results are reported using a 28 nm Bulk CMOS technology provided by TSMC. Using a 2 MHz carrier input signal and an implant depth of 1 cm, the data rate is up to 1.33 Mbit/s with a 50% duty cycle, while the minimum average power consumption is cut-down to 3.3 μW in the typical corner.
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36
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Kashani Z, Ilham SJ, Kiani M. Design and Optimization of Ultrasonic Links With Phased Arrays for Wireless Power Transmission to Biomedical Implants. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:64-78. [PMID: 34986100 PMCID: PMC9131469 DOI: 10.1109/tbcas.2022.3140591] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Ultrasound (US) is an attractive modality for wireless power transfer (WPT) to biomedical implants with millimeter (mm) dimensions. To compensate for misalignments in WPT to a mm-sized implant (or powering a network of mm-sized implants), a US transducer array should electronically be driven in a beamforming fashion (known as US phased array) to steer focused US beams at different locations. This paper presents the theory and design methodology of US WPT links with phased arrays and mm-sized receivers (Rx). For given constraints imposed by the application and fabrication, such as load (RL) and focal distance (F), the optimal geometries of a US phased array and Rx transducer, as well as the optimal operation frequency (fc) are found through an iterative design procedure to maximize the power transfer efficiency (PTE). An optimal figure of merit (FoM) related to PTE is proposed to simplify the US array design. A design example of a US link is presented and optimized for WPT to a mm-sized Rx with a linear array. In measurements, the fabricated 16-element array (10.9×9×1.7 mm3) driven by 100 V pulses at fc of 1.1 MHz with optimal delays for focusing at F = 20 mm generated a US beam with a pressure output of 0.8 MPa. The link could deliver up to 6 mW to a ∼ 1 mm3 Rx with a PTE of 0.14% (RL = 850 Ω). The beam steering capability of the array at -45o to 45o angles was also characterized.
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A Circularly Polarized Implantable Rectenna for Microwave Wireless Power Transfer. MICROMACHINES 2022; 13:mi13010121. [PMID: 35056286 PMCID: PMC8777898 DOI: 10.3390/mi13010121] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/09/2022] [Accepted: 01/10/2022] [Indexed: 02/04/2023]
Abstract
A circularly polarized implantable antenna integrated with a voltage-doubled rectifier (abbr., rectenna) is investigated for microwave wireless power transfer in the industrial, scientific, and medical (ISM) band of 2.4–2.48 GHz. The proposed antenna is miniaturized with the dimensions of 7.5 mm × 7.5 mm × 1.27 mm by etching four C-shaped open slots on the patch. A rectangular slot truncated diagonally is cut to improve the circular polarization performance of the antenna. The simulated impedance bandwidth in a three-layer phantom is 30.4% (1.9–2.58 GHz) with |S11| below −10 dB, and the 3-dB axial-ratio bandwidth is 16.9% (2.17–2.57 GHz). Furthermore, a voltage-doubled rectifier circuit that converts RF power to DC power is designed on the back of the antenna. The simulated RF-to-DC conversion efficiency can be up to 45% at the input power of 0 dBm. The proposed rectenna was fabricated and measured in fresh pork to verify the simulated results and evaluate the performance of wireless power transfer.
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38
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Das R, Langou S, Le TT, Prasad P, Lin F, Nguyen TD. Electrical Stimulation for Immune Modulation in Cancer Treatments. Front Bioeng Biotechnol 2022; 9:795300. [PMID: 35087799 PMCID: PMC8788921 DOI: 10.3389/fbioe.2021.795300] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 12/17/2021] [Indexed: 12/17/2022] Open
Abstract
Immunotherapy is becoming a very common treatment for cancer, using approaches like checkpoint inhibition, T cell transfer therapy, monoclonal antibodies and cancer vaccination. However, these approaches involve high doses of immune therapeutics with problematic side effects. A promising approach to reducing the dose of immunotherapeutic agents given to a cancer patient is to combine it with electrical stimulation, which can act in two ways; it can either modulate the immune system to produce the immune cytokines and agents in the patient's body or it can increase the cellular uptake of these immune agents via electroporation. Electrical stimulation in form of direct current has been shown to reduce tumor sizes in immune-competent mice while having no effect on tumor sizes in immune-deficient mice. Several studies have used nano-pulsed electrical stimulations to activate the immune system and drive it against tumor cells. This approach has been utilized for different types of cancers, like fibrosarcoma, hepatocellular carcinoma, human papillomavirus etc. Another common approach is to combine electrochemotherapy with immune modulation, either by inducing immunogenic cell death or injecting immunostimulants that increase the effectiveness of the treatments. Several therapies utilize electroporation to deliver immunostimulants (like genes encoded with cytokine producing sequences, cancer specific antigens or fragments of anti-tumor toxins) more effectively. Lastly, electrical stimulation of the vagus nerve can trigger production and activation of anti-tumor immune cells and immune reactions. Hence, the use of electrical stimulation to modulate the immune system in different ways can be a promising approach to treat cancer.
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Affiliation(s)
- Ritopa Das
- Department of Biomedical Engineering, University of Connecticut, Mansfield, CT, United States
| | - Sofia Langou
- Department of Physiology and Neurobiology, University of Connecticut, Mansfield, CT, United States
| | - Thinh T. Le
- Department of Mechanical Engineering, University of Connecticut, Mansfield, CT, United States
| | - Pooja Prasad
- Department of Cell and Molecular Biology, University of Connecticut, Mansfield, CT, United States
| | - Feng Lin
- Department of Mechanical Engineering, University of Connecticut, Mansfield, CT, United States
| | - Thanh D. Nguyen
- Department of Biomedical Engineering, University of Connecticut, Mansfield, CT, United States
- Department of Mechanical Engineering, University of Connecticut, Mansfield, CT, United States
- Institute of Materials Science, University of Connecticut, Mansfield, CT, United States
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Khalifa A, Lee S, Molnar AC, Cash S. Injectable wireless microdevices: challenges and opportunities. Bioelectron Med 2021; 7:19. [PMID: 34937565 PMCID: PMC8697496 DOI: 10.1186/s42234-021-00080-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 11/22/2021] [Indexed: 11/21/2022] Open
Abstract
In the past three decades, we have witnessed unprecedented progress in wireless implantable medical devices that can monitor physiological parameters and interface with the nervous system. These devices are beginning to transform healthcare. To provide an even more stable, safe, effective, and distributed interface, a new class of implantable devices is being developed; injectable wireless microdevices. Thanks to recent advances in micro/nanofabrication techniques and powering/communication methodologies, some wireless implantable devices are now on the scale of dust (< 0.5 mm), enabling their full injection with minimal insertion damage. Here we review state-of-the-art fully injectable microdevices, discuss their injection techniques, and address the current challenges and opportunities for future developments.
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Affiliation(s)
- Adam Khalifa
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Sunwoo Lee
- Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA
| | | | - Sydney Cash
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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40
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Zhang Y, Demosthenous A. Integrated Circuits for Medical Ultrasound Applications: Imaging and Beyond. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2021; 15:838-858. [PMID: 34665739 DOI: 10.1109/tbcas.2021.3120886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Medical ultrasound has become a crucial part of modern society and continues to play a vital role in the diagnosis and treatment of illnesses. Over the past decades, the development of medical ultrasound has seen extraordinary progress as a result of the tremendous research advances in microelectronics, transducer technology and signal processing algorithms. However, medical ultrasound still faces many challenges including power-efficient driving of transducers, low-noise recording of ultrasound echoes, effective beamforming in a non-linear, high-attenuation medium (human tissues) and reduced overall form factor. This paper provides a comprehensive review of the design of integrated circuits for medical ultrasound applications. The most important and ubiquitous modules in a medical ultrasound system are addressed, i) transducer driving circuit, ii) low-noise amplifier, iii) beamforming circuit and iv) analog-digital converter. Within each ultrasound module, some representative research highlights are described followed by a comparison of the state-of-the-art. This paper concludes with a discussion and recommendations for future research directions.
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41
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Kopyl S, Surmenev R, Surmeneva M, Fetisov Y, Kholkin A. Magnetoelectric effect: principles and applications in biology and medicine- a review. Mater Today Bio 2021; 12:100149. [PMID: 34746734 PMCID: PMC8554634 DOI: 10.1016/j.mtbio.2021.100149] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/05/2021] [Accepted: 10/08/2021] [Indexed: 12/26/2022] Open
Abstract
Magnetoelectric (ME) effect experimentally discovered about 60 years ago remains one of the promising research fields with the main applications in microelectronics and sensors. However, its applications to biology and medicine are still in their infancy. For the diagnosis and treatment of diseases at the intracellular level, it is necessary to develop a maximally non-invasive way of local stimulation of individual neurons, navigation, and distribution of biomolecules in damaged cells with relatively high efficiency and adequate spatial and temporal resolution. Recently developed ME materials (composites), which combine elastically coupled piezoelectric (PE) and magnetostrictive (MS) phases, have been shown to yield very strong ME effects even at room temperature. This makes them a promising toolbox for solving many problems of modern medicine. The main ME materials, processing technologies, as well as most prospective biomedical applications will be overviewed, and modern trends in using ME materials for future therapies, wireless power transfer, and optogenetics will be considered.
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Affiliation(s)
- S. Kopyl
- Department of Physics & CICECO - Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
| | - R. Surmenev
- Physical Materials Science and Composite Materials Centre, Research School of Chemistry & Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
- Piezo- and Magnetoelectric Materials Research & Development Centre, Research School of Chemistry & Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
| | - M. Surmeneva
- Physical Materials Science and Composite Materials Centre, Research School of Chemistry & Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
- Piezo- and Magnetoelectric Materials Research & Development Centre, Research School of Chemistry & Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
| | - Y. Fetisov
- Research & Education Centre ‘Magnetoelectric Materials and Devices’, MIREA – Russian Technological University, Moscow, Russia
| | - A. Kholkin
- Department of Physics & CICECO - Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Piezo- and Magnetoelectric Materials Research & Development Centre, Research School of Chemistry & Applied Biomedical Sciences, National Research Tomsk Polytechnic University, Tomsk, Russia
- School of Natural Sciences and Mathematics, Ural Federal University, Ekaterinburg, Russia
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Turner BL, Senevirathne S, Kilgour K, McArt D, Biggs M, Menegatti S, Daniele MA. Ultrasound-Powered Implants: A Critical Review of Piezoelectric Material Selection and Applications. Adv Healthc Mater 2021; 10:e2100986. [PMID: 34235886 DOI: 10.1002/adhm.202100986] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/15/2021] [Indexed: 12/14/2022]
Abstract
Ultrasound-powered implants (UPIs) represent cutting edge power sources for implantable medical devices (IMDs), as their powering strategy allows for extended functional lifetime, decreased size, increased implant depth, and improved biocompatibility. IMDs are limited by their reliance on batteries. While batteries proved a stable power supply, batteries feature relatively large sizes, limited life spans, and toxic material compositions. Accordingly, energy harvesting and wireless power transfer (WPT) strategies are attracting increasing attention by researchers as alternative reliable power sources. Piezoelectric energy scavenging has shown promise for low power applications. However, energy scavenging devices need be located near sources of movement, and the power stream may suffer from occasional interruptions. WPT overcomes such challenges by more stable, on-demand power to IMDs. Among the various forms of WPT, ultrasound powering offers distinct advantages such as low tissue-mediated attenuation, a higher approved safe dose (720 mW cm-2 ), and improved efficiency at smaller device sizes. This study presents and discusses the state-of-the-art in UPIs by reviewing piezoelectric materials and harvesting devices including lead-based inorganic, lead-free inorganic, and organic polymers. A comparative discussion is also presented of the functional material properties, architecture, and performance metrics, together with an overview of the applications where UPIs are being deployed.
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Affiliation(s)
- Brendan L. Turner
- Joint Department of Biomedical Engineering North Carolina State University and University of North Carolina Chapel Hill, 911 Oval Dr. Raleigh NC 27695 USA
| | - Seedevi Senevirathne
- The Patrick G Johnston Centre for Cancer Research Queen's University 97 Lisburn Rd Belfast BT9 7AE UK
| | - Katie Kilgour
- Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA
| | - Darragh McArt
- The Patrick G Johnston Centre for Cancer Research Queen's University 97 Lisburn Rd Belfast BT9 7AE UK
| | - Manus Biggs
- Centre for Research in Medical Devices National University of Ireland Newcastle Road Galway H91 W2TY Ireland
| | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA
| | - Michael A. Daniele
- Joint Department of Biomedical Engineering North Carolina State University and University of North Carolina Chapel Hill, 911 Oval Dr. Raleigh NC 27695 USA
- Department of Electrical and Computer Engineering North Carolina State University 890 Oval Dr. Raleigh NC 27695 USA
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Costa T, Shi C, Tien K, Elloian J, Cardoso FA, Shepard KL. An Integrated 2D Ultrasound Phased Array Transmitter in CMOS With Pixel Pitch-Matched Beamforming. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2021; 15:731-742. [PMID: 34260357 DOI: 10.1109/tbcas.2021.3096722] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Emerging non-imaging ultrasound applications, such as ultrasonic wireless power delivery to implantable devices and ultrasound neuromodulation, require wearable form factors, millisecond-range pulse durations and focal spot diameters approaching 100 μm with electronic control of its three-dimensional location. None of these are compatible with typical handheld linear array ultrasound imaging probes. In this work, we present a 4 mm × 5 mm 2D ultrasound phased array transmitter with integrated piezoelectric ultrasound transducers on complementary metal-oxide-semiconductor (CMOS) integrated circuits, featuring pixel-level pitch-matched transmit beamforming circuits which support arbitrary pulse duration. Our direct integration method enabled up to 10 MHz ultrasound arrays in a patch form-factor, leading to focal spot diameter of ∼200 μm, while pixel pitch-matched beamforming allowed for precise three-dimensional positioning of the ultrasound focal spot. Our device has the potential to provide a high-spatial resolution and wearable interface to both powering of highly-miniaturized implantable devices and ultrasound neuromodulation.
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Conta G, Libanori A, Tat T, Chen G, Chen J. Triboelectric Nanogenerators for Therapeutic Electrical Stimulation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2007502. [PMID: 34014583 DOI: 10.1002/adma.202007502] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/03/2020] [Indexed: 06/12/2023]
Abstract
Current solutions developed for the purpose of in and on body (IOB) electrical stimulation (ES) lack autonomous qualities necessary for comfortable, practical, and self-dependent use. Consequently, recent focus has been placed on developing self-powered IOB therapeutic devices capable of generating therapeutic ES for human use. With the recent invention of the triboelectric nanogenerator (TENG), harnessing passive human biomechanical energy to develop self-powered systems has allowed for the introduction of novel therapeutic ES solutions. TENGs are especially effective at providing ES for IOB therapeutic systems given their bioconformability, low cost, simple manufacturability, and self-powering capabilities. Due to the key role of naturally induced electrical signals in many physiological functions, TENG-induced ES holds promise to provide a novel paradigm in therapeutic interventions. The aim here is to detail research on IOB TENG devices applied for ES-based therapy in the fields of regenerative medicine, neurology, rehabilitation, and pharmaceutical engineering. Furthermore, considering TENG-produced ES can be measured for sensing applications, this technology is paving the way to provide a fully autonomous personalized healthcare system, capable of IOB energy generation, sensing, and therapeutic intervention. Considering these grounds, it seems highly relevant to review TENG-ES research and applications, as they could constitute the foundation and future of personalized healthcare.
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Affiliation(s)
- Giorgio Conta
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Alberto Libanori
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Trinny Tat
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Guorui Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Jun Chen
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
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Cho J, Seong G, Chang Y, Kim C. Energy-Efficient Integrated Circuit Solutions Toward Miniaturized Closed-Loop Neural Interface Systems. Front Neurosci 2021; 15:667447. [PMID: 34135727 PMCID: PMC8200530 DOI: 10.3389/fnins.2021.667447] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 04/13/2021] [Indexed: 11/29/2022] Open
Abstract
Miniaturized implantable devices play a crucial role in neural interfaces by monitoring and modulating neural activities on the peripheral and central nervous systems. Research efforts toward a compact wireless closed-loop system stimulating the nerve automatically according to the user's condition have been maintained. These systems have several advantages over open-loop stimulation systems such as reduction in both power consumption and side effects of continuous stimulation. Furthermore, a compact and wireless device consuming low energy alleviates foreign body reactions and risk of frequent surgical operations. Unfortunately, however, the miniaturized closed-loop neural interface system induces several hardware design challenges such as neural activity recording with severe stimulation artifact, real-time stimulation artifact removal, and energy-efficient wireless power delivery. Here, we will review recent approaches toward the miniaturized closed-loop neural interface system with integrated circuit (IC) techniques.
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Affiliation(s)
- Jaeouk Cho
- Biomedical Energy-Efficient Electronics Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Geunchang Seong
- Biomedical Energy-Efficient Electronics Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Yonghee Chang
- Biomedical Energy-Efficient Electronics Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Chul Kim
- Biomedical Energy-Efficient Electronics Laboratory, Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.,KAIST Institute for Health Science and Technology, Daejeon, South Korea
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46
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Ultra-compact dual-band smart NEMS magnetoelectric antennas for simultaneous wireless energy harvesting and magnetic field sensing. Nat Commun 2021; 12:3141. [PMID: 34035237 PMCID: PMC8149822 DOI: 10.1038/s41467-021-23256-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 04/13/2021] [Indexed: 11/12/2022] Open
Abstract
Ultra-compact wireless implantable medical devices are in great demand for healthcare applications, in particular for neural recording and stimulation. Current implantable technologies based on miniaturized micro-coils suffer from low wireless power transfer efficiency (PTE) and are not always compliant with the specific absorption rate imposed by the Federal Communications Commission. Moreover, current implantable devices are reliant on differential recording of voltage or current across space and require direct contact between electrode and tissue. Here, we show an ultra-compact dual-band smart nanoelectromechanical systems magnetoelectric (ME) antenna with a size of 250 × 174 µm2 that can efficiently perform wireless energy harvesting and sense ultra-small magnetic fields. The proposed ME antenna has a wireless PTE 1–2 orders of magnitude higher than any other reported miniaturized micro-coil, allowing the wireless IMDs to be compliant with the SAR limit. Furthermore, the antenna’s magnetic field detectivity of 300–500 pT allows the IMDs to record neural magnetic fields. Wireless implantable medical devices (IMDs) are hamstrung by both size and efficiency required for wireless power transfer. Here, Zaeimbashi et al. present a magnetoelectric nano-electromechanical systems that can harvest energy and sense weak magnetic fields like those arising from neural activity.
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Shi C, Andino-Pavlovsky V, Lee SA, Costa T, Elloian J, Konofagou EE, Shepard KL. Application of a sub-0.1-mm 3 implantable mote for in vivo real-time wireless temperature sensing. SCIENCE ADVANCES 2021; 7:7/19/eabf6312. [PMID: 33962948 PMCID: PMC8104878 DOI: 10.1126/sciadv.abf6312] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 03/18/2021] [Indexed: 05/17/2023]
Abstract
There has been increasing interest in wireless, miniaturized implantable medical devices for in vivo and in situ physiological monitoring. Here, we present such an implant that uses a conventional ultrasound imager for wireless powering and data communication and acts as a probe for real-time temperature sensing, including the monitoring of body temperature and temperature changes resulting from therapeutic application of ultrasound. The sub-0.1-mm3, sub-1-nW device, referred to as a mote, achieves aggressive miniaturization through the monolithic integration of a custom low-power temperature sensor chip with a microscale piezoelectric transducer fabricated on top of the chip. The small displaced volume of these motes allows them to be implanted or injected using minimally invasive techniques with improved biocompatibility. We demonstrate their sensing functionality in vivo for an ultrasound neurostimulation procedure in mice. Our motes have the potential to be adapted to the distributed and localized sensing of other clinically relevant physiological parameters.
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Affiliation(s)
- Chen Shi
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
| | | | - Stephen A Lee
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Tiago Costa
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
- Department of Microelectronics, Delft University of Technology, 2628 CD Delft, Netherlands
| | - Jeffrey Elloian
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
| | - Elisa E Konofagou
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
- Department of Radiology, Columbia University, New York, NY 10032, USA
| | - Kenneth L Shepard
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA.
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
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Khalifa A, Eisape A, Coughlin B, Cash S. A simple method for implanting free-floating microdevices into the nervous tissue. J Neural Eng 2021; 18. [PMID: 33827069 DOI: 10.1088/1741-2552/abf590] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 04/07/2021] [Indexed: 12/20/2022]
Abstract
Objective. Free-floating implantable neural interfaces are an emerging powerful paradigm for mapping and modulation of brain activity. Minuscule wirelessly-powered devices have the potential to provide minimally-invasive interactions with neurons in chronic research and medical applications. However, these devices face a seemingly simple problem-how can they be placed into nervous tissue rapidly, efficiently and in an essentially arbitrary location?Approach. We introduce a novel injection tool and describe a controlled injection approach that minimizes damage to the tissue.Main results.To validate the needle injectable tool and the presented delivery approach, we evaluate the spatial precision and rotational alignment of the microdevices injected into agarose, brain, and sciatic nerve with the aid of tissue clearing and MRI imaging. In this research, we limited the number of injections into the brain to four per rat as we are using microdevices that are designed for an adult head size on a rat model. We then present immunohistology data to assess the damage caused by the needle.Significance. By virtue of its simplicity, the proposed injection method can be used to inject microdevices of all sizes and shapes and will do so in a fast, minimally-invasive, and cost-effective manner. As a result, the introduced technique can be broadly used to accelerate the validation of these next-generation types of electrodes in animal models.
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Affiliation(s)
- Adam Khalifa
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Adebayo Eisape
- Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD 21218, United States of America
| | - Brian Coughlin
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
| | - Sydney Cash
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, United States of America
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Shon A, Brakel K, Hook M, Park H. Fully Implantable Plantar Cutaneous Augmentation System for Rats Using Closed-loop Electrical Nerve Stimulation. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2021; 15:326-338. [PMID: 33861705 DOI: 10.1109/tbcas.2021.3072894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Plantar cutaneous feedback plays an important role in stable and efficient gait, by modulating the activity of ankle dorsi- and plantar-flexor muscles. However, central and peripheral nervous system trauma often decrease plantar cutaneous feedback and/or interneuronal excitability in processing the plantar cutaneous feedback. In this study, we tested a fully implantable neural recording and stimulation system augmenting plantar cutaneous feedback. Electromyograms were recorded from the medial gastrocnemius muscle for stance phase detection, while biphasic stimulation pulses were applied to the distal-tibial nerve during the stance phase to augment plantar cutaneous feedback. A Bluetooth low energy and a Qi-standard inductive link were adopted for wireless communication and wireless charging, respectively. To test the operation of the system, one intact rat walked on a treadmill with the electrical system implanted into its back. Leg kinematics were recorded to identify the stance phase. Stimulation was applied, with a 250-ms onset delay from stance onset and 200-ms duration, resulting in the onset at 47.58 ± 2.82% of stance phase and the offset at 83.49 ± 4.26% of stance phase (Mean ± SEM). The conduction velocity of the compound action potential (31.2 m/s and 41.6 m/s at 1·T and 2·T, respectively) suggests that the evoked action potential was characteristic of an afferent volley for cutaneous feedback. We also demonstrated successful wireless charging and system reset functions. The experimental results suggest that the presented implantable system can be a valuable neural interface tool to investigate the effect of plantar cutaneous augmentation on gait in a rat model.
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50
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Eickhoff S, Jarvis JC. Pulse Shaping Strategies for Electroceuticals: A Comprehensive Survey of the Use of Interphase Gaps in Miniature Stimulation Systems. IEEE Trans Biomed Eng 2021; 68:1658-1667. [PMID: 33651679 DOI: 10.1109/tbme.2021.3063029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Interphase gaps (IPGs) are among the most commonly suggested pulse shape variations to try to enhance neural stimulation efficiency by reducing the action potential (AP) suppressing effect of an early anodic hyperpolarization. The majority of published literature on the effect of IPGs is based on investigations of monopolar stimulation configurations. However, many contemporary neuromodulation applications including the emerging field of electroceutical devices operate in a bipolar electrode configuration. METHODS We investigated the effect of IPGs and asymmetric biphasic current controlled pulses with reduced anodic amplitude on neural activation in both principal electrode configurations in a rodent in-vivo nerve muscle preparation. RESULTS In the monopolar electrode configuration, our findings of 10.9 ± 1.5% decreased stimulation amplitude with 200 μs IPGs in biphasic pulses of 40 μs phase width are in agreement with published literature in this configuration. Surprisingly, using the bipolar configuration, opposite effects of IPGs were observed and neural activation required up to 18.6 ± 3.1% (phase width 100 μs, IPG = 1000 μs) higher amplitudes. Electroneurogram recordings of the stimulated nerve revealed temporal differences in AP generation between the monopolar and bipolar configuration. In the bipolar configuration excitation first occurred in response to the middle field transition of biphasic pulses. CONCLUSION This is the first study to report consistently increased amplitude requirements with IPGs in bipolar stimulation configurations. SIGNIFICANCE Our findings must be taken into consideration when designing stimulation waveforms for neuromodulation devices that operate in a bipolar mode to avoid increased amplitude requirements that result in increased energy consumption.
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