Project Summary/Abstract: The full impact of personalized medicine can only be realized through rapid and convenient access to individual biomarker data both at home and in the clinic. Biosensors that enable on-demand quantification of drugs, hormones, and other clinically relevant analytes have long been promised as the next breakthrough for facilitating precision medicine. While point-of-care and continuous glucose monitors have drastically improved outcomes for diabetic patients, there has been virtually no clinical adoption of biosensors for other target analytes despite tremendous potential for impact in areas such as therapeutic drug monitoring, post-operative surveillance, and continuous hormone monitoring. Beyond enzymatic glucose sensors, electrochemical aptamer based (EAB) sensors comprise the only other biosensing modality that has been broadly validated in vivo. Despite demonstration of continuous sensing for over a dozen different analytes in animal models, no EAB sensor has seen validation in human subjects due to lack of integration into deployable devices. Therefore, a major need exists to bridge the gap between biosensor research and the type of devices needed for real patient impact. We postulate that initial impact is particularly well-aligned with immediate needs for high-frequency monitoring of drug and hormone concentrations in obstetric and pediatric populations, as clinical trial data are often sparse with regard to these patients despite various physiological variations that can lead to drastic interpatient variability in analyte concentrations. Our central hypothesis is that through both device-oriented and novel signal-transduction innovations, EAB sensors can achieve the performance needed to translate them from the research bench to a format that is clinically deployable for point-of-care and/or continuous biosensing. Specifically, we postulate that advancements in shelf storage, off-the-shelf stability, sensor interrogation, and sensor protection will allow EAB sensors to be characterized and validated in integrated devices suitable for human subject testing. We plan to pursue validation of our central hypothesis by (1) in vitro validating EAB sensors operating in an at- home test strip format, (2) demonstrating the continuous operation of EAB sensors in a wearable device for >1 week and (3) validating these integrated devices in human subjects for model EAB sensors targeting the narrow therapeutic index antibiotic vancomycin. This proposal will usher in the long-awaited validation of EAB sensors for the on-demand monitoring of analytes in human subjects, serving as a foundation for further clinical adoption of this sensing modality as the technology developed here is expanded to other analytes and applications in personalized medicine.