◆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.
