Nanomanufacturing of Smart and Connected Bioelectronics Through Nanomaterial Printing, Hybrid Material Integration, and Soft Packaging

Recent advances in microfabrication technologies, materials engineering, and packaging strategies have enabled the development of electronics that are flexible and conformable to the human skin. However, achieving the compatibilities with living tissues came at the costs of low-yield and low-scale manufacturing techniques, including high-vacuum processes and photolithography, limiting the use of such electronics to conceptual demonstrations. Here, we introduce a comprehensive strategy to manufacture soft bioelectronics that combines nanomaterial printing, hybrid material integration, and soft-material packaging. We leverage nanomaterial printing using aerosols as the new enabling manufacturing technique with the potential to resolve the issues inherent with bio-interfaced thin-film electronics based on MEMS processes. Biocompatible graphene and polyimide are chosen as the conductive and insulating layer for the printed electrodes for their superb electrical properties-the conductivity of the printed graphene is 5×10
⁴
S/m, and the dielectric constant of the printed polyimide is 3.0. Also, the combination of graphene, silver nanoparticles, and polyimide enables a successful printing of nanomembrane circuit interconnects. The advanced performance of the printed electrode with integrated soft electronics is described within the context of electrophysiology. Examples include monitoring real-time electrocardiograms, electromyograms, galvanic skin responses, and applications in human-machine interfaces and animal research.