Electrochemical amplification strategies in DNA nanosensors

Abstract

Electrochemical DNA nanosensors exploit the intrinsic property of ssDNA to hybridize to its complementary sequence and this selective hybridization event can be translated into detectable electrochemical signals following electrochemical amplification. This review describes some of the advanced electrochemical signal amplification strategies in DNA detection relying on specific sequence hybridization with focus on electro-active intercalating reagents, primary and secondary reporter DNA probes and 'de-amplification' of signals derived from nanopores and nanochannels. These amplification strategies elegantly achieve extremely low detection limits of pico- to femtomolarity concentration and zeptomolar amount of DNAs and high specificity responses without the use of multi-step polymerase chain reaction (PCR) procedures or high sensitivity instrumentation.