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Abstract Neurologic and neuropsychiatric disorders substantially impact the pediatric population, but there is a lack of dedicated devices for monitoring the developing brain in animal models, leading to gaps in mechanistic understanding of how brain functions emerge and their disruption in disease states. Due to the small size, fragility, and high water content of immature neural tissue, as well as the absence of a hardened skull to mechanically support rigid devices, conventional neural interface devices are poorly suited to acquire brain signals without inducing damage. Here, the authors design conformable, implantable, conducting polymer‐based probes (NeuroShanks) for precise targeting in the developing mouse brain without the need for skull‐attached, rigid mechanical support structures. These probes enable the acquisition of high spatiotemporal resolution neurophysiologic activity from superficial and deep brain regions across unanesthetized behavioral states without causing tissue disruption or device failure. Once implanted, probes are mechanically stable and permit precise, stable signal monitoring at the level of the local field potential and individual action potentials. These results support the translational potential of such devices for clinically indicated neurophysiologic recording in pediatric patients. Additionally, the role of organic bioelectronics as an enabling technology to address questions in developmental neuroscience is revealed. 

Abstract Modern implantable bioelectronics demand soft, biocompatible components that make robust, low‐impedance connections with the body and circuit elements. Concurrently, such technologies must demonstrate high efficiency, with the ability to interface between the body's ionic and external electronic charge carriers. Here, a mixed‐conducting suture, the e‐suture, is presented. Composed of silk, the conducting polymer poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), and insulating jacketing polymers,the resulting e‐suture has mixed‐conducting properties at the interface with biological tissue as well as effective insulation along its length. The e‐suture can be mechanically integrated into electronics, enabling the acquisition of biopotentials such as electrocardiograms, electromyograms, and local field potentials (LFP). Chronic, in vivo acquisition of LFP with e‐sutures remains stable for months with robust brain activity patterns. Furthermore, e‐sutures can establish electrophoretic‐based local drug delivery, potentially offering enhanced anatomical targeting and decreased side effects associated with systemic administration, while maintaining an electrically conducting interface for biopotential monitoring. E‐sutures expand on the conventional role of sutures and wires by providing a soft, biocompatible, and mechanically sound structure that additionally has multifunctional capacity for sensing, stimulation, and drug delivery. 

Abstract Organic electronics can be biocompatible and conformable, enhancing the ability to interface with tissue. However, the 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, vertical internal ion-gated organic electrochemical transistor (vIGT), is based on a transistor architecture that incorporates a vertical channel and a miniaturized hydration access conduit to enable megahertz-signal-range operation within densely packed integrated arrays in the absence of crosstalk. These transistors demonstrated long-term stability in physiologic media, and were used to generate high-performance integrated circuits. We leveraged the high-speed and low-voltage operation of vertical internal ion-gated organic electrochemical transistors to develop alternating-current-powered conformable circuitry to acquire and wirelessly communicate signals. 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.