Xiaomin Xu1
Tsinghua University1
In the fast-evolving landscape of decentralized and personalized healthcare, the need for ultraflexible biosensing systems that integrate seamlessly with the human body is growing rapidly. This presents significant challenges in devising ultraflexible configurations that accommodate multiple sensors and designing high-performance sensing components that remain stable over long periods. This talk addresses device engineering toward skin-integrated electronics and implantable neural interfaces for chronic applications. We first introduce ultraflexible organic optoelectronics functioning as sensing components and energy harvesters as wearables [1,2]. To bridge soft tissues and rigid electronics, we introduce an ultrathin hydrogel film as the electronics/skin interface to overcome their stark disparities [3]. We then demonstrate a highly conductive tattoo electrode that can be placed on the skin or injected into the epidermis layer for real-time and precise electrophysiological signal recordings [4]. Finally, strategies toward highly conductive hydrogel and the application potential as chronic neural interfaces will be discussed.<br/><b>References:</b><br/>[1] a) X. Xu, T. Someya*, et al. Thermally stable, highly efficient, ultraflexible organic photovoltaics. <i>Proc. Natl. Acad. Sci. U.S.A. </i><b>2018</b>,<i> </i>115, 4589. b) H. Jinno, K. Fukuda, X. Xu, T. Someya*, etc. Stretchable and waterproof elastomer-coated organic photovoltaics for washable electronic textile applications. <i>Nat. Energy </i><b>2017</b>,<i> </i>2, 780.<br/>[2] Z. Lou, X. Xu*, et al. Near-infrared organic photodetectors toward skin-integrated photoplethysmography-electrocardiography multimodal sensing system. <i>Adv. Sci.</i> <b>2023</b>, 2304174.<br/>[3] S. Cheng, X. Xu*, et al. Ultrathin hydrogel films toward breathable skin-integrated electronics. <i>Adv. Mater</i>. <b>2023</b>, 35, 2206793.<br/>[4] B. Wei, X. Xu*, et al. Ultraflexible tattoo electrodes for epidermal and in vivo electrophysiological recording. <i>Cell Rep. Phys. Sci.</i> <b>2023</b>, 4, 101335.