Conductive Polymer-Based Bioelectronic Platforms toward Sustainable and Biointegrated Devices: A Journey from Skin to Brain across Human Body Interfaces

Abstract

Over the last few years, organic bioelectronics has experienced an exponential growth with applications encompassing platforms for tissue engineering, drug delivery systems, implantable, and wearable sensors. Although reducing the physical and mechanical mismatch with the human tissues allows to increase the coupling efficiency, several challenges are still open in terms of matching biological curvature, size, and interface stiffness. In this context, the replacement of bulky with more flexible and conformable devices is required, implying the transition from inorganic conventional electronics to organic electronics. Indeed, the advent of organic materials in bioelectronics, due to the indisputable benefits related to biocompatibility, flexibility, and electrical properties, has granted superior coupling properties with human tissues increasing the performances of both sensing and stimulation platforms. In this review the ease of functionalization and patterning of conductive polymers (CPs) will be analyzed as a strategy that enables the fabrication of platforms with high structural flexibility ranging from the macro to the micro/nano-scales, leading to the increase of devices sensitivity. Drawing from the concept of biomimicry, the human body tissues interfaces will be explored through an ideal journey starting from organic platforms for epidermal sensing and stimulation. Then, devices capable of establishing a dynamic coupling with the heart will be reviewed and finally, following the circulatory system and crossing the blood-brain barrier, the brain will be reached and novel sensing and computing implants advances that pave the way to the possibility to emulate as well as to interact with the neural functions will be analyzed.