3D Printable Hydrogel Bioelectronic Interfaces for Various Organs

Bioelectronic interfaces require intimate and prolonged functional communication with highly fragile and sensitive tissues or organs, and therefore, high biocompatibility and low foreign body responses. Clearly noticeable in the progressive advances in bioelectronic interfaces in recent decades, bioelectronic interfaces have been continuously innovated in both designs and materials to achieve tissue-matching properties to minimize foreign body responses while providing desired electrophysiological functionalities such as recordings and stimulations. Owing to the unique tissue-matching properties, hydrogels have been one of the most promising materials to provide biocompatible long-term interfacing with biological tissues. Here, we report 3D-printed hydrogel bioelectronic interface consists of highly stretchable and soft hydrogels. The unique set of 3D-printable hydrogel inks allows facile and flexible one-step additive manufacturing of bioelectronic interfaces with diverse designs. To validate tissue-matching properties and biocompatibility of the 3D-printed hydrogel bioelectronic interfaces, we perform systematic mechanical and electrical characterizations and in vivo evaluations based on rat models. The resulted hydrogel bioelectronic interfaces will not only provide a promising platform for bioelectronic devices and treatments but also inspire the future development of functional hydrogel devices and machines.