Silver(I) ions and cysteine detection based on photoinduced electron transfer mediated by cytosine-Ag+-cytosine base pairs

Upon formation of cytosine-Ag+-cytosine base pairs as a mediator for the photoinduced electron transfer, the fluorescence of FAM-labeled DNA was quenched and the fluorescence emission wavelength exhibited a red shift. Based on these phenomena a novel dual-output fluorescent DNA sensor for Ag+ ions and cysteine detection was developed.