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Bioelectronic devices and components made from soft, polymer-based and hybrid electronic materials form natural interfaces with the human body. Advances in the molecular design of stretchable dielectric, conducting and semiconducting polymers, as well as their composites with various metallic and inorganic nanoscale or microscale materials, have led to more unobtrusive and conformal interfaces with tissues and organs. Nonetheless, technical challenges associated with functional performance, stability and reliability of integrated soft bioelectronic systems still remain. This Review discusses recent progress in biomedical applications of soft organic and hybrid electronic materials, device components and integrated systems for addressing these challenges. We first discuss strategies for achieving soft and stretchable devices, highlighting molecular and materials design concepts for incorporating intrinsically stretchable functional materials. We next describe design strategies and considerations on wearable devices for on-skin sensing and prostheses. Moving beneath the skin, we discuss advances in implantable devices enabled by materials and integrated devices with tissue-like mechanical properties. Finally, we summarize strategies used to build standalone integrated systems and whole-body networks to integrate wearable and implantable bioelectronic devices with other essential components, including wireless communication units, power sources, interconnects and encapsulation.
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Achieving tissue-level softness on stretchable electronics through a generalizable soft interlayer design
Abstract Soft and stretchable electronics have emerged as highly promising tools for biomedical diagnosis and biological studies, as they interface intimately with the human body and other biological systems. Most stretchable electronic materials and devices, however, still have Young’s moduli orders of magnitude higher than soft bio-tissues, which limit their conformability and long-term biocompatibility. Here, we present a design strategy of soft interlayer for allowing the use of existing stretchable materials of relatively high moduli to versatilely realize stretchable devices with ultralow tissue-level moduli. We have demonstrated stretchable transistor arrays and active-matrix circuits with moduli below 10 kPa—over two orders of magnitude lower than the current state of the art. Benefiting from the increased conformability to irregular and dynamic surfaces, the ultrasoft device created with the soft interlayer design realizes electrophysiological recording on an isolated heart with high adaptability, spatial stability, and minimal influence on ventricle pressure. In vivo biocompatibility tests also demonstrate the benefit of suppressing foreign-body responses for long-term implantation. With its general applicability to diverse materials and devices, this soft-interlayer design overcomes the material-level limitation for imparting tissue-level softness to a variety of bioelectronic devices.
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- Award ID(s):
- 2011854
- PAR ID:
- 10435153
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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