Nanoparticle carrying a single probe for target DNA detection and single nucleotide discrimination.

The identification of single nucleotide mutations with specific disease and single nucleotide polymorphisms (SNPs) among individuals is increasingly important for diagnosis of genetic disease, prediction of disease resistance or predispositions, as well as administration of drug dosages and design of personalized medicine. In this study, we demonstrated a convenient yet useful colorimetric quantitative DNA assay method with high single nucleotide discrimination for both center and end-mismatched sequences. The detection limit of our method is 75 fmol of DNA sample. Even for mixed DNA sample with low percentages of matched targets, this method shows good probe selectivity and zero false positive detection. Finally, the ease of operation and compatibility with existing molecular biology toolbox makes this method a potential low-cost alternative in scientific and clinical diagnostic application.