A novel label-free strategy for the ultrasensitive miRNA-182 detection based on MoS₂/Ti₃C₂ nanohybrids

MicroRNAs (miRNAs) are regarded as a large variety of cancer-related biomarkers, and they have attracted wide attentions in recent years. In this work, a novel label-free strategy for the ultrasensitive detection of miRNA-182 (a typical biomarker for lung cancer) based on MoS₂/Ti₃C₂ nanohybrids was suggested. Firstly, modified glassy carbon electrode (GCE) with massive active sites and good electronic conductivity was prepared for biosensing. Then, based on this platform a descent signal in differential pulse voltammetry (DPV) peak current could be observed with the addition of probe RNA with negative charge. Thereafter, with the hybridization of target miRNA-182 with immobilized probe RNA and the swelling-induced breakage of Au-S bonds between RNA and the electrode surface, the characteristic DPV signals increase were found. In particular, this biosensing platform for special miRNAs possessed a good linear detection window in a range from 1 fM to 0.1 nM with a detection limit of 0.43 fM.