Characterization of genomic SNP via colorimetric detection using a single gold nanoprobe

ABSTRACT Identification of specific nucleic acid sequences mediated by gold nanoparticles derivatized thiol-modified oligonucleotides (Au-nanoprobes) has been proven a useful tool in molecular diagnostics. Here, we demonstrate that, upon optimization, detection may be simplified via use of a single Au-nanoprobe to detect a single nucleotide polymorphism (SNP) in homo- or heterozygote condition. We validate this non-cross-linking approach through the analysis of 20 clinical samples using a single specific Au-nanoprobe for a SNP in FTO gene against direct DNA sequencing. Sensitivity, specificity and limit of detection (LOD) were determined and statistical differences calculated by one-way analysis of variance (ANOVA) and a post hoc Tukey’s test to ascertain whether there were any differences between Au-nanoprobe genotyped groups. For the first time, we show that utilization of a single Au-nanoprobe to detect SNP for each genetic status (