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Abstract Transparent microelectrodes have recently emerged as a promising approach for crosstalk‐free multifunctional electrical and optical biointerfacing. High‐performance flexible platforms that allow seamless integration with soft tissue systems for such applications are urgently needed. Here, silver nanowires (Ag NWs)‐based transparent microelectrode arrays (MEAs) and interconnects are designed to meet this demand. The nanowire networks exhibit a high optical transparency >90.0% at 550 nm, and superior mechanical stability up to 100,000 bending cycles at 5 mm radius. The Ag NWs microelectrodes preserve low normalized electrochemical impedance of 3.4–15 Ω cm2at 1 kHz, and the interconnects demonstrate excellent sheet resistance (Rsh) of 4.1–25 Ω sq−1. In vivo histological analysis reveals that the Ag NWs structures are biocompatible. Studies on Langendorff‐perfused mouse and rat hearts demonstrate that the Ag NWs MEAs enable high‐fidelity real‐time monitoring of heart rhythm during co‐localized optogenetic pacing and optical mapping. This proof‐of‐concept work illustrates that the solution‐processed, transparent, and flexible Ag NWs structures are a promising candidate for the next‐generation of large‐area multifunctional biointerfaces for interrogating complex biological systems in basic and translational research.
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Semiconductor Nanowire‐Based Cellular and Subcellular Interfaces
Abstract The highly intricate structures of biological systems make the precise probing of biological behaviors at the cellular‐level particularly difficult. As an advanced toolset capable of exploring diverse biointerfaces, high‐aspect‐ratio nanowires stand out with their unique mechanical, optical, and electrical properties. Specifically, semiconductor nanowires show much promise in their tunability and feasibility for synthesis and fabrication. Thus far, semiconductor nanowires have shown favorable results in deciphering biological communications and translating this cellular language through the nanowire‐based biointerfaces. In this perspective, the synthesis and fabrication methods for different kinds of nanowires and nanowire‐based structures are first surveyed. Next, several cellular‐level nanowire‐enabled applications in biophysical dynamics probing, physiological or biochemical sensing, and biological activity modulation are highlighted. Then, the progress of functionalized nanowires in drug delivery and bioenergy production is reviewed. Finally, the current limitations of nanowires and an outlook into the next generation of nanowire‐based devices at the biointerfaces are concluded.
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- PAR ID:
- 10363655
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 11
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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