A novel VS2 nanosheet-based biosensor for rapid fluorescence detection of cytochrome c

Abstract

A novel ultrasensitive sensing system for rapid fluorescence detection of cytochrome c (cyt c) was proposed by combining aptamer-based bioassay with VS₂ nanosheets. VS₂ nanosheets with high fluorescence quenching ability were synthesized by the solution route. A cyt c-binding aptamer was tagged with the fluorescent dye carboxy fluorescein (FAM), acting as the probe. VS₂ nanosheets can adsorb the probe and quench its fluorescence efficiently. However, the fluorescence of the probe was retained when it was incubated with cyt c and then mixed with VS₂ nanosheet solution. The proposed sensing system shows high selectivity and sensitivity, giving a linear range of 0.75 nM to 50 μM, and a limit of detection of 0.50 nM.