A label-free kissing complex-induced fluorescence sensor for DNA and RNA detection by using DNA-templated silver nanoclusters as a signal transducer

Riboswitches are complex folded RNA domains that serve as receptors for specific metabolites which are widely used in biosensor design. They are comprised of a biosensor that includes the binding site for a small ligand and they respond to association with this ligand by undergoing a conformational change. In the present study, we report on the integration of silver nanoclusters (AgNCs) and riboswitches for the expanding of the application of a kissing complex-induced sensor (KCIS). This strategy allows for simple tethering of the specific oligonucleotides stabilizing the AgNCs to the nucleic acid probes. We specifically apply the tunable riboswitches properties of this strategy to demonstrate the multiplexes analysis of DNA and RNA. This is a new concept for oligonucleotides detection, and opens an opportunity for design of more novel biosensors based on the kissing complex-induced strategy.