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Title: Skin‐Inspired Porous Mesh Bioelectronics with Built‐In Multifunctionality for Concurrently Monitoring Heart Electrical and Mechanical Functions
The skin exhibits nonlinear mechanics, which is initially soft and stiffens rapidly as being stretched to prevent large deformation‐induced injuries. Developing skin‐interfaced bioelectronics with skin‐inspired nonlinear mechanical behavior, together with multiple other desired features (breathable, antibacterial, and sticky), is desirable yet challenging. Herein, this study reports the design, fabrication, and biomedical application of porous mesh bioelectronics that can simultaneously achieve these features. On the one hand, porous serpentine meshes of polyimide (PI) are designed and fabricated under the guidance of theoretical simulations to provide skin‐like nonlinear mechanics and high breathability. On the other hand, ultrasoft, sticky, and antibacterial polydimethylsiloxane (PDMS) is developed through epsilon polylysine (ε‐PL) modifications, which are currently lacking in the field. Here,ε‐PL‐modified PDMS is spray‐coated on PI meshes to form the core–shell structures without blocking their pores to offer ultrasoft, sticky, and antibacterial skin interfaces. And rationally designed porous hybrid meshes can not only retain skin‐like nonlinear mechanical properties but also enable the integration of both soft and hard bioelectronic components for various healthcare applications. As the exemplar example, this study integrates soft silver nanowires (AgNWs) based electrophysiological sensors and rigid commercial accelerometers on multifunctional porous meshes for concurrently monitoring heart electrical and mechanical functions to provide comprehensive information on the evolving heart status.  more » « less
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Advanced Functional Materials
Medium: X
Sponsoring Org:
National Science Foundation
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