1A) 5, 9. Upon target binding, the aptamer undergoes a conformational change, producing an easily-measurable shift in electrochemical signal 1. In this sensor architecture, a target-recognizing aptamer is modified with a redox reporter and covalently attached to a gold electrode using a self-assembled monolayer (Fig. Finally, we demonstrate the use of non-blood proxy media to achieve calibration without the need to collect fresh whole blood.Įlectrochemical aptamer-based (EAB) sensors are a specific class of aptasensors that, uniquely, support high-frequency 1, 2 real-time molecular measurements 3, 4 directly in complex biological media, including unprocessed, undiluted bodily fluids 5, 6. We likewise find that, because blood age impacts the sensor response, calibrating in freshly collected blood can improve quantification. Comparing titrations collected at room and body temperature, we find that matching the temperature of calibration curve collection to the temperature used during measurements improves quantification by reducing differences in sensor gain and binding curve midpoint. Using freshly-collected, undiluted whole blood at body temperature as both our calibration and measurement conditions, we demonstrate accuracy of better than ± 10% for the measurement of our test bed drug, vancomycin. Here we explore quantification using EAB sensors, examining the impact of media selection and temperature on measurement performance. Electrochemical aptamer-based (EAB) sensors support the real-time, high frequency measurement of pharmaceuticals and metabolites in-situ in the living body, rendering them a potentially powerful technology for both research and clinical applications.

Alex downs scida