Disposable Electrochemical DNA Biosensors

Abstract

Electrochemical DNA hybridization biosensors have been a major research field for over a decade, because their rapid, simple, and low-cost detection capabilities provide several advantages to clinical, forensic, and environmental monitoring. Basically, DNA biosensors convert the Watson–Crick base-pair recognition event into a readable analytical signal. The miniaturization of electrochemical DNA biosensors enabled the mass production of disposable sensor strips. These sensor strips have gradually taken the place of the conventional three-electrode system consisting of bulky working, reference, and counter electrodes, and beakers with a large amount of buffer and analyte solution volume, mostly ranging between 1 and 2 mL. Nowadays, two important electrode materials are in widespread use for disposable sensor technology: carbon and gold (Au). Au is the noble metal of choice for screen printing of disposable sensor strips. Au strips offer a very favorable electron-transfer kinetics and a wide anodic potential range.