Wearable Bioelectronics: Opportunities for Chemistry
The practice of human health care may be on the cusp of a revolution, driven by an unprecedented level of personalization enabled by advances in technology, specifically, the transformation of wearable devices from curiosities that provide qualitative information for fitness enthusiasts to sophisticated systems that produce clinical-grade data for physicians.A recent and highly visible example is the Apple Watch Series 4, a platform released in September 2018 that features electrocardiogram measurement capabilities cleared by the US Food and Drug Administration (FDA).Companies such as MC10, iRhythm, Vital Connect, GE Healthcare, and Philips offer nextgeneration devices characterized by intimate skin interfaces and FDA-approved multimodal functionalities, with the potential to allow for medical care that is highly customized to the individual.The designs range from rigid modules mounted to the body with straps and tapes, to thin, stretchable systems that adhere directly onto the skin, much like adhesive bandages or temporary tattoos.New government initiatives in the US, such as those associated with the NextFlex Alliance, the BRAIN initiative, the SPARC program at the NIH, and the Biotechnology Office at DARPA, support research programs in relevant areas via robust levels of funding, although now likely surpassed by combined investments from foundations, venture capital firms, and large corporations.The resulting accelerated rates of technology development and deployment serve as nucleation points for large, growing programs in adjacent areas, most prominently in medical data analytics at Verily, Apple, Philips, Facebook, Intel, Samsung, and others.The outcomes of these collective activities have the potential to lead to unprecedented basic insights into human physiology, with wide-ranging, positive consequences for the cost, efficacy, speed, and global availability of personalized medical care.Successful efforts will directly address an overarching grand challenge for the 21st century, defined by the US National Academy of Engineering as the need for advances in "...the acquisition, management, and use of information in health...".This special issue highlights the central role of chemical research in establishing the foundations for wearable bioelectronics with advanced capabilities in measurements of physiological state, performed continuously, outside of hospital and laboratory settings but with quantitative correspondence to clinical gold standards.The Accounts that appear in this issue summarize recent research on key aspects, ranging from constituent materials to novel sensors, advanced power supply systems, and skin-compatible integrated platforms.The first area represents a primary focus for the materials chemistry community, where a collection of papers covers, for example, progress in stretchable block copolymers and conjugated organics for structural materials and active layers, respectively, and associated techniques in processing such as spin-casting, printing, and vapor phase deposition onto both planar and textile substrates.Other papers focus on micro-and nanoscale