Single-nucleotide polymorphism detection with "wire-like" DNA probes that display quasi "on-off" digital action.

Establishing a reliable genotyping protocol is a critical matter in post-sequence genetics. In this article, we describe a highly sensitive electrochemical detection of complementary DNAs (up to 43-mer) based on hole transport with molecular-scale, "wire-like" DNA probes. The presence of a single-base mismatch in the DNA duplexes caused a dramatic decrease in the electrochemical response.