Stand-Alone Conformable Implantable Bioelectronics Based on Internal Ion-Gated Organic Electrochemical Transistors

It is increasingly appreciated that individual variability can strongly affect response to clinical treatments, motivating approaches that enable long-term monitoring of physiologic signals and delivery of responsive therapeutics. Implanted bioelectronic devices are often critical components of such approaches. The incompatibility of traditional electronic components with physiologic media, risk of device-related tissue disruption, and limited means by which to interface and power implanted devices are key hurdles. Organic electronics can be biocompatible and conformable, enhancing the ability to interface with tissue. However, limitations of speed and integration have thus far necessitated reliance on silicon- based technologies for advanced processing, data transmission, and device powering. Here, we create a stand-alone, conformable, fully organic bioelectronic device capable of realizing these functions. This device is based on a novel transistor architecture that incorporates a vertical channel and miniaturized hydration access conduit to enable MHz signal range operation within densely packed integrated arrays in the absence of crosstalk (vertical internal ion-gated organic electrochemical transistor, vIGT). vIGTs demonstrated long-term stability in physiologic media, and were used to generate high performance multi-stage amplifiers, oscillators, multiplexers, and rectifiers. We leveraged the high speed and low voltage operation of vIGTs to link them with an ion-based powering and data transmission approach that provides power to the transistor in the form of MHz range alternating current and permits signal extraction via modulation of this applied current. The resultant stand-alone device was implanted in freely moving rodents to acquire, process, and transmit neurophysiologic brain signals. Such fully organic devices have the potential to expand the utility and accessibility of bioelectronics to a wide range of clinical and societal applications.