Electrochemical DNA biosensor using a disposable electrochemical printed (DEP) chip for the detection of SNPs from unpurified PCR amplicons

In this study, we are reporting for the first time the elucidation of single nucleotide polymorphisms (SNPs) of clinically important alleles from consenting human subjects using a disposable electrochemical printed (DEP) chip in connection with differential pulse voltammetry (DPV) and a redox active molecule Hoechst 33258 [H33258, 2′-(4-hydroxyphenyl)-5-(4-methyl-1-piperazinyl)-2,5′-bi(1H-benzimidazole)]. Post-PCR products were analyzed directly without any purification process. The aggregation of the DNA–H33258 complex causes a significant drop in the peak current intensity of H33258 oxidation. The phenomenon of DNA aggregation induced by H33258 in addition to changes in anodic current peak are used to detect SNPs. Since laborious probe immobilization was not required, our biosensor offers several benefits due to its simplicity and rapid response as a promising device for genetic analysis.