A method for SNP detection using MoS2@AuNPs and SYBR Green I in combination with enzyme digestion

Abstract

Single-nucleotide polymorphisms (SNPs) in a gene sequence are markers for a variety of human diseases. SNP detection methods are time-consuming, need laboratory-scale settings, and are expensive. A simple, rapid and label-free method for detecting SNPs was developed in this study. SG (SYBR Green I), DNA sequences, and molybdenum disulfide–gold nanoparticles (MoS₂@AuNPs) were used in this sensing system for a proof-of-principle study. DNA was immobilized on the surface of MoS₂@AuNPs in order to remove the nonspecific probe displacement and false-positive signals using 10% Tween 80. MoS₂@AuNPs quenched the fluorescence from SG intercalated into the DNA duplex. The SG fluorescence signals from the matched and mismatched DNA duplex were significantly different after the addition of MoS₂. HapII can recognize the enzyme digestion site in the DNA sequence and further improve the effect of SNP detection. Therefore, this method can clearly distinguish SNPs in DNA sequences.