On the Design, Fabrication, and Operation of Electrochemical Aptamer-Based Sensors

Electrochemical aptamer-based (EAB) sensors are the only high-frequency, real-time molecular measurement approach reported to date that is simultaneously both (1) selective enough to deploy in situ in the body and (2) independent of the chemical reactivity of its target, rendering it generalizable to the measurement of a wide range of analytes. To date, for example, a half dozen research groups have demonstrated the ability of EAB sensors to support few-second to subsecond resolved, multihour measurements of drugs and biomarkers in the veins, brains, and solid peripheral tissues of live rats. Motivated by the scientific and clinical applications these real-time, highly time-resolved in vivo measurements enable, significant literature has explored methods for improving the design, fabrication, and operation of EAB sensors. Here, we critically review this literature in an effort to identify what we believe are the most promising of these approaches and which are the areas of EAB sensor design, fabrication, and operation that remain to be profitably explored.