Tissue-like electrophysiological electrode interface construction by multiple crosslinked polysaccharide-based hydrogel

A reliable electrophysiological electrode interface (EEI) between bioelectronic devices and biological tissues is indispensable to achieve the high fidelity recording of bioelectricity . However, there is an inherent tradeoff among EEI's electrochemical characteristics, mechanical properties and biocompatibility when considering the desired nanostructure and optimum composition . Here, we proposed a mechanically matched, highly conductive and biocompatible EEI, a tissue-like metal-doped hydrogel which could enable excellent electro-biosensing, by bringing disulfide modified silver nanowires into difunctional hyaluronan/carboxymethyl chitosan composite. The intensity of cortical signals at specific frequency domain recorded by the hydrogel-based EEI is doubled, which is significant for the diagnosis of epilepsy. Furthermore, the natural gel matrix could lead to seamless bio-integration between EEI and the tissue site of interest, minimizing signal dissipation without causing obvious inflammatory response. Overall, the EEI we designed contributes to improving tissue-device integration as well as bioelectronic device's performance and further leads to more effective human-computer interfaces.