3D printed bioelectronic scaffolds with soft tissue-like stiffness

Abstract 3D printing is a leading technique for fabricating tissue engineering scaffolds that facilitate native cellular behavior. Engineering scaffolds to possess functional properties like electronic conductivity is the first step towards integrating new technological capabilities like stimulating or monitoring cellular activity beyond the traditionally presented biophysical and biochemical cues. However, these bioelectronic scaffolds have been largely underdeveloped since the majority of electrically conducting materials possess high stiffness values outside the physiological range and that may negatively impact desired cell behavior. Here, we present methods of 3D printing poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) hydrogel scaffolds and provide techniques to achieve stiffness relevant to many soft tissues (<100 kPa). Structures were confirmed as ideal tissue scaffolds by maintaining biostability and promoting high cell viability, appropriate cell morphology, and proliferation. With these findings, we contribute a customizable 3D platform that provides favorable soft cellular microenvironments and envision it to be adaptable to several bioelectronic applications. Competing Interest Statement The authors have declared no competing interest.