A novel CdTe quantum dots probe amplified resonance light scattering signals to detect microRNA-122

We report a rapid and facile resonance light scattering (RLS) technique that utilizes CdTe quantum dots (CdTe QDs) probe to detect microRNA-122. The RLS sensor is ingeniously designed with P1 and P2 , two cDNA sequence probes with partially complementary sequences to miRNA-122. The amine-modified P1 and P2 are coupled to the surface of QDs to form functional QDs-P1 and QDs-P2 conjugates, which are collectively referred to as QDs-P. The cDNAs hybridize with the target miRNA to rapidly induce the self-assembly of QDs probe and change RLS intensity. The proposed technique can detect miRNA-122 within 40   min. RLS intensity is enhanced in proportion with miRNA-122 concentrations of 0.16–4.80   nM and has a low detection limit of 9.4   pM. In addition, the assay satisfactorily detects miRNAs in human serum samples. Thus, the assay has considerable potential for the analysis of other interesting tumor makers.