(Invited) Designed DNA Nano-Switches As Sensitive Electrochemical Biosensors

Abstract

Functional nucleic acid receptors (aptamers) have emerged as effective and robust recognition elements for state-of-the-art biosensors. Analytical readouts from aptamer-based biosensors (whether optical, electrochemical, or otherwise) derive primarily from global-scale conformational changes induced in the aptamer domain by analyte binding. Herein, we describe a unique biosensor design principle that represents a distinct alternative to this paradigm; particularly we demonstrate the ready applicability of this design principle in the de novo creation of electrochemical sensors for a clinical analyte of current interest. The function of the class of biosensors we describe, termed “DNA nano-switches”, is designed to depend on the integrity of duplex DNA-mediated charge transfer between an electrode and a redox label.[1] Thomas, J. M.; Chakraborty, B.; Sen, D.; Yu, H.-Z. J. Am. Chem. Soc. 2012, 134, 13823–13833.[2] Tang, Y.; Ge, B.; Sen, D.; Yu, H.-Z. Chem. Soc. Rev. 2014, 43, 518–529[3] Ma, F.; Qi, L.; Einarson, O.; Sen, D.; Yu, H.-Z. Anal. Chem. 2019, 91, 8244−8251. Figure 1