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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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Surface Wrinkling for Flexible and Stretchable Sensors
Abstract Recent advances in nanolithography, miniaturization, and material science, along with developments in wearable electronics, are pushing the frontiers of sensor technology into the large‐scale fabrication of highly sensitive, flexible, stretchable, and multimodal detection systems. Various strategies, including surface engineering, have been developed to control the electrical and mechanical characteristics of sensors. In particular, surface wrinkling provides an effective alternative for improving both the sensing performance and mechanical deformability of flexible and stretchable sensors by releasing interfacial stress, preventing electrical failure, and enlarging surface areas. In this study, recent developments in the fabrication strategies of wrinkling structures for sensor applications are discussed. The fundamental mechanics, geometry control strategies, and various fabricating methods for wrinkling patterns are summarized. Furthermore, the current state of wrinkling approaches and their impacts on the development of various types of sensors, including strain, pressure, temperature, chemical, photodetectors, and multimodal sensors, are reviewed. Finally, existing wrinkling approaches, designs, and sensing strategies are extrapolated into future applications.
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- Award ID(s):
- 2134664
- PAR ID:
- 10376181
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 18
- Issue:
- 42
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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