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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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Advanced Electrical and Optical Microsystems for Biointerfacing
Electrical and optical biointerfaces have contributed considerably to understanding biological systems. Recent advances in biocompatible materials, structure designs, and fabrication techniques have established flexible and minimally invasive electronic/optoelectronic platforms that laminate onto targeted surface regions or implant into precise locations of biosystems to monitor and control various biological processes at cell, tissue, and organ levels. Herein, recent progress in advanced biointegrated electrical and optical platforms is discussed. An overview of materials and device designs to form flexible and even stretchable electrodes is presented. Strategies to reduce tissue damage and foreign‐body response to improve chronic stability are described. State‐of‐the‐art wearable and implantable microsystems with/without wireless capabilities for bioelectrical sensing and stimulation, optical recording and modulation, and multimodal operation are highlighted. In conclusion, a discussion of the remaining obstacles for future research in these areas is provided.
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- Award ID(s):
- 2011093
- PAR ID:
- 10171832
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 2
- Issue:
- 9
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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