A "turn-on" DNA-scaffolded silver-nanocluster probe for detection of tumor-related mRNA.

A novel and "turn-on" DNA-silver nanocluster probe (DNA/AgNCs) was developed that can detect the level of breast tumor-related mRNA markers: cyclin D1 mRNA. The fluorescence of DNA/AgNCs probe rendered a "turn-on" response based on the secondary structure changes induced by the target strand. In the presence of target chain, the fluorescence enhances in a concentration-dependent manner, which enables the quantitative detection of analytes. By this method, a detection limit of 2.1 nM and a linear range of 15-125 nM were achieved. In addition, the probe displays excellent discrimination between a perfectly complementary target and single-base mismatch targets, providing an alternative approach for quick and specific recognition and quantification of mRNA or DNA.