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Ding B, Teng C, Wang Y, Wang Y, Jiang H, Sun Y, Guo J, Dai S. A Simplified Method for the Preparation of Highly Conductive and Flexible Silk Nanofibrils/MXene Membrane. Materials (Basel) 2023; 16:6960. [PMID: 37959557 PMCID: PMC10648990 DOI: 10.3390/ma16216960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 10/22/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023]
Abstract
Silk nanofibers (SNF) have great applications in high-performance functional nanocomposites due to their excellent mechanical properties, biocompatibility, and degradability. However, the preparation of SNF by traditional methods often requires the use of some environmentally harmful or toxic reagents, limiting its application in green chemistry. In this paper, we successfully prepared SNF using natural silk as raw material and solvent stripping technology by adjusting the solvent concentration and solution ratio (the diameter of about 120 nm). Using the above SNFs as raw materials, SNF membranes were prepared by vacuum filtration technology. In addition, we prepared an SNF/MXene nanocomposite material with excellent humidity sensitivity by simply coating MXene nanosheets with silk fibers. The conductivity of the material can approach 1400.6 S m-1 with excellent mechanical strength (51.34 MPa). The SNF/MXene nanocomposite material with high mechanical properties, high conductivity, and green degradability can be potentially applied in the field of electromagnetic interference (EMI) shielding, providing a feasible approach for the development of functional nanocomposite materials.
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Affiliation(s)
- Bohan Ding
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Chao Teng
- College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Yanxiang Wang
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Yongbo Wang
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Haotian Jiang
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Yue Sun
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Jinghe Guo
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
| | - Shichao Dai
- Carbon Fiber Engineering Research Center, School of Materials Science and Engineering, Shandong University, Jinan 250061, China
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2
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Wang XR, Meng ZY, Wang XF, Cai WL, Liu K, Wang D. Silk Nanofibril-Palygorskite Composite Membranes for Efficient Removal of Anionic Dyes. Nanomaterials (Basel) 2023; 13:247. [PMID: 36678001 PMCID: PMC9864787 DOI: 10.3390/nano13020247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/27/2022] [Accepted: 01/03/2023] [Indexed: 06/17/2023]
Abstract
To develop membrane materials with good performance for water purification that are green and low cost, this work reports an organic-inorganic composite membrane composed of silk nanofibrils (SNFs) and palygorskite (PGS). To improve the stability of the the composite membrane, genipin was used as a crosslinking agent to induce the conformational transition of SNF chains from random coils to β-sheets, reducing the swelling and hydrolysis of the membrane. The separation performance can be adjusted by tailoring the component ratio of the nanomaterial. The results showed that these membranes can effectively remove anionic dyes from water, and they exhibit excellent water permeability. The SNF-based membrane had strong mechanical and separation properties, and the PGS could tune the structure of composite membranes to enhance their permeability, so this green composite membrane has good prospects in water treatment and purification applications.
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Affiliation(s)
- Xu-rui Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Zhe-yi Meng
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Xue-fen Wang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Wei-long Cai
- Qingyuan Innovation Laboratory, Quanzhou 362801, China
| | - Ke Liu
- Key Laboratory of Textile Fiber and Products, Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Intelligent Textile Materials and Application, Wuhan Textile University, Wuhan 430200, China
| | - Dong Wang
- Key Laboratory of Textile Fiber and Products, Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Intelligent Textile Materials and Application, Wuhan Textile University, Wuhan 430200, China
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3
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Perera D, Wang Q, Schniepp HC. Multi-Point Nanoindentation Method to Determine Mechanical Anisotropy in Nanofibrillar Thin Films. Small 2022; 18:e2202065. [PMID: 35780468 DOI: 10.1002/smll.202202065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/26/2022] [Indexed: 06/15/2023]
Abstract
Biomaterials with outstanding mechanical properties, including spider silk, wood, and cartilage, often feature an oriented nanofibrillar structure. The orientation of nanofibrils gives rise to a significant mechanical anisotropy, which is extremely challenging to characterize, especially for microscopically small or inhomogeneous samples. Here, a technique utilizing atomic force microscope indentation at multiple points combined with finite element analysis to sample the mechanical anisotropy of a thin film in a microscopically small area is reported. The system studied here is the tape-like silk of the Chilean recluse spider, which entirely consists of strictly oriented nanofibrils giving rise to a large mechanical anisotropy. The most detailed directional nanoscale structure-property characterization of spider silk to date is presented, revealing the tensile and transverse elastic moduli as 9 and 1 GPa, respectively, and the binding strength between silk nanofibrils as 159 ± 13 MPa. Furthermore, based on this binding strength, the nanofibrils' surface energy is derived as 37 mJ m-2 , and concludes that van der Waals forces play a decisive role in interfibrillar binding. Due to its versatility, this technique has many potential applications, including early disease diagnostics, as underlying pathological conditions can alter the local mechanical properties of tissues.
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Affiliation(s)
- Dinidu Perera
- Department of Applied Science, William & Mary, P.O. Box 8795, Williamsburg, VA, 23187-8795, USA
| | - Qijue Wang
- Department of Applied Science, William & Mary, P.O. Box 8795, Williamsburg, VA, 23187-8795, USA
| | - Hannes C Schniepp
- Department of Applied Science, William & Mary, P.O. Box 8795, Williamsburg, VA, 23187-8795, USA
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Hu Z, Yan S, Li X, You R, Zhang Q, Kaplan DL. Natural Silk Nanofibril Aerogels with Distinctive Filtration Capacity and Heat-Retention Performance. ACS Nano 2021; 15:8171-8183. [PMID: 33848124 DOI: 10.1021/acsnano.1c00346] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Nanofibrous aerogels have been extensively developed as multifunctional substrates in a wide range of fields. Natural silk nanofibrils (SNFs) are an appealing biopolymer due to their natural abundance, mechanical toughness, biodegradability, and excellent biocompatibility. However, fabricating 3D SNF materials with mechanical flexibility remains a challenge. Herein, SNF-based aerogels with controlled structures and well mechanical resilience were prepared. SNFs were extracted from silkworm silks by mechanical disintegration based on an all-aqueous system. The nanofibrils network and hierarchical cellular structure of the aerogels were tuned by the assembly of SNFs and foreign poly(vinyl alcohol) (PVA). The SNF aerogels exhibited an ultralow density (as low as 2.0 mg·cm-3) and well mechanical properties with a structure allowing for large deformations. These SNF aerogels demonstrated a reversible compression and stress retention after 100 cycles of compression. Furthermore, the resulting aerogels were used for air filtration and showed efficient filtration performance with a high dust-holding capacity and low resistance. Moreover, an extremely low thermal conductivity of 0.028 W·(m·K)-1 was achieved by the aerogel, showing its potential for use in heat-retention applications. This study provides a useful strategy for exploring the use of natural silks in 3D aerogels and offers options for developing filtration materials and ultralight heat-retention materials.
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Affiliation(s)
- Zhanao Hu
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Textile Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Shuqin Yan
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Textile Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Xiufang Li
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Textile Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Renchuan You
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Textile Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - Qiang Zhang
- State Key Laboratory of New Textile Materials and Advanced Processing Technologies, School of Textile Science and Engineering, Wuhan Textile University, Wuhan 430200, China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
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Liu X, Zhang W, Lin Z, Meng Z, Shi C, Xu Z, Yang L, Liu XY. Coupling of Silk Fibroin Nanofibrils Enzymatic Membrane with Ultra-Thin PtNPs/Graphene Film to Acquire Long and Stable On-Skin Sweat Glucose and Lactate Sensing. Small Methods 2021; 5:e2000926. [PMID: 34927831 DOI: 10.1002/smtd.202000926] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/23/2020] [Indexed: 06/14/2023]
Abstract
The applications of enzymatic biosensors are largely limited by their relatively poor stability and short lifespan. Herein, a bio-active porous enzymatic nanofiber (PEN) membrane composed of silk fibroin nanofibrils (SFNFs) and enzymes is developed to effectively retain the enzymes in the 3D space. The 3D functional scaffolds formed by SFNFs can immobilize enzymes and provide a large surface area for molecular/ion diffusion and biochemical reactions. The PEN membrane is subsequently attached to an ultra-thin PtNPs/graphene (Pt-G) nanocomposite film to facilitate the electron transport between the enzymes and electrodes, permitting highly effective glucose and lactate sensing with long and stable performance. The as-assembled glucose and lactate sensors demonstrate high sensitivity, good cyclic reproducibility, and in particular long-term stability of up to 25 and 23.6 h, respectively. These glucose sensors have a working life that is ≈1.25-times longer than that of the best available sensors reported so far. Moreover, a wearable platform based on the sensors is developed for real-time analysis of sweat during outdoor exercising to transmit signals to a mobile handset. The high sensitivity, comfort and long-term stability of the device can benefit for long-term in-line surveillance of physiological conditions.
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Affiliation(s)
- Xiaotian Liu
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Wenli Zhang
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Zaifu Lin
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Zhaohui Meng
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Chenyang Shi
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Zhijun Xu
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Likun Yang
- College of Materials, Research Institute for Biomimetics and Soft Matter, College of Physical Science and Engineering, School of Electronic Science and Engineering, Shenzhen Research Institute of Xiamen University, Xiamen University, 422 Siming Nan Road, Xiamen, 361005, China
| | - Xiang Yang Liu
- Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore, 117542, Singapore
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Xiao Y, Liu Y, Zhang W, Qi P, Ren J, Pei Y, Ling S. Formation, Structure, and Mechanical Performance of Silk Nanofibrils Produced by Heat-Induced Self-Assembly. Macromol Rapid Commun 2020; 42:e2000435. [PMID: 33196127 DOI: 10.1002/marc.202000435] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/29/2020] [Indexed: 12/25/2022]
Abstract
The heat-induced self-assembly of silk fibroin (SF) is studied by combing fluorescence assessment, infrared nanospectroscopy, wide-angle X-ray scattering, and Derjaguin-Muller-Toporov coupled with atomic force microscopy. Several fundamental issues regarding the formation, structure, and mechanical performance of silk nanofibrils (SNFs) under heat-induced self-assembly are discussed. Accordingly, SF in aqueous solution is rod-like in shape and not micellar. The formation of SNFs occurs through nucleation-dependent aggregation, but the assembly period is variable and irregular. SF shows inherent fractal growth, and this trend is critical for the short-term assembly. The long-term assembly of SF, however, mainly involves an elongation growth process. SNFs produced by different methods, such as ethanol treatment and heat incubation, have similar secondary structure and mechanical properties. These investigations improve the in-depth understanding of fundamental issues related to self-assembly of SNFs, and thus provide inspiration and guidance in designing of silk nanomaterials.
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Affiliation(s)
- Yuelong Xiao
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Yawen Liu
- School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Wenwen Zhang
- School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Ping Qi
- School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Jing Ren
- School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
| | - Ying Pei
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Shengjie Ling
- School of Physical Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Shanghai, 201210, China
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7
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Abstract
Protein nanostructures in living organisms have attracted intense interests in biology and material science owing to their intriguing abilities to harness ion transportation for matter/signal transduction and bioelectricity generation. Silk nanofibrils, serving as the fundamental building blocks for silk, not only have the advantages of natural abundance, low cost, biocompatibility, sustainability, and degradability but also play a key role in mechanical toughness and biological functions of silk fibers. Herein, cationic silk nanofibrils (SilkNFs), with an ultrathin thickness of ∼4 nm and a high aspect ratio up to 500, were successfully exfoliated from natural cocoon fibers via quaternization followed by mechanical homogenization. Being positively charged in a wide pH range of 2-12, these cationic SilkNFs could combine with different types of negatively charged biological nanofibrils to produce asymmetric ionic membranes and aerogels that have the ability to tune ion translocation. The asymmetric ionic aerogels could create an electric potential as high as 120 mV in humid ambient air, whereas asymmetric ionic membranes could be used in ionic rectification with a rectification ratio of 5.2. Therefore, this green exfoliation of cationic SilkNFs may provide a biological platform of nanomaterials for applications as diverse as ion electronics, renewable energy, and sustainable nanotechnology.
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Affiliation(s)
- Weiqing Yang
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- College of Chemistry and Chemical Engineering, Qingdao University, 308 Ningxia Road, Qingdao, Shandong 266071, P.R. China
| | - Lili Lv
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- Center of Material and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China
| | - Xiankai Li
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- Center of Material and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China
| | - Xiao Han
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- Center of Material and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China
| | - Mingjie Li
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- Center of Material and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China
| | - Chaoxu Li
- Group of Biomimetic Smart Materials, CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Songling Road 189, Qingdao 266101, P.R. China
- Center of Material and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, P.R. China
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Zhao F, Peydayesh M, Ying Y, Mezzenga R, Ping J. Transition Metal Dichalcogenide-Silk Nanofibril Membrane for One-Step Water Purification and Precious Metal Recovery. ACS Appl Mater Interfaces 2020; 12:24521-24530. [PMID: 32368892 DOI: 10.1021/acsami.0c07846] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
With the rapid worldwide industrial development, large amounts of pollutants such as heavy metals are discharged into the water sources, causing a huge threat to living beings. To mitigate this issue, there is an urgent need for new water treatment strategies. Inspired by a natural shell nacre structure and a multidimensional hybrid concept, we demonstrate multilayered inorganic-organic hybrid membranes using metallic molybdenum disulfide (MoS2) as two-dimensional transition metal dichalcogenide nanosheets and one-dimensional silk nanofibrils for water purification. Because of its possessing negatively charged layers and interaction sites, the hybrid film could adsorb metal ions and dyes from water. The separation performance can be tuned by changing the component ratios of these two nanomaterials. During filtration, due to the reducing effect of the MoS2 nanosheets, precious metal ions are reduced to their nanoparticle form without any further thermal or chemical treatments. In addition to the one-step removal and recovery of metal ions, the hybrid membranes exhibit excellent potential for the determination and removal of different dyes from water. The results of this research can open up an effective and green avenue for water purification and recovery of metal ions dissolved in water.
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Affiliation(s)
- Fengnian Zhao
- School of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P. R. China
| | - Mohammad Peydayesh
- Department of Health Sciences and Technology, ETH Zurich, Zurich 8092, Switzerland
| | - Yibin Ying
- School of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P. R. China
- Zhejiang A&F University, Hangzhou 311300, P. R. China
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology, ETH Zurich, Zurich 8092, Switzerland
- Department of Materials, ETH Zurich, Zurich 8093, Switzerland
| | - Jianfeng Ping
- School of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P. R. China
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Ling S, Li C, Jin K, Kaplan DL, Buehler MJ. Liquid Exfoliated Natural Silk Nanofibrils: Applications in Optical and Electrical Devices. Adv Mater 2016; 28:7783-90. [PMID: 27352291 DOI: 10.1002/adma.201601783] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 05/17/2016] [Indexed: 05/02/2023]
Abstract
A method to directly extract silk nanofibrils from native silk fibers at the single nanofibrils scale is reported. The resulting silk nanofibrils, which retain structural features and physical properties of native silk fibers, show potential utility in optical and electronic devices.
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Affiliation(s)
- Shengjie Ling
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Chunmei Li
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Kai Jin
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA.
| | - Markus J Buehler
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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