Fluorescence “turn-off/turn-on” biosensing of metal ions by gold nanoclusters, folic acid and reduced graphene oxide

Metal ions homeostasis plays an important role in biological processes. The ability to detect the concentration of metal fluids is often challenged by obvious interference or competitive binding nature other alkaline metals ions. Common analytical techniques employed for detection are electrochemical, fluorescence and colorimetric methods. However, most reported sensors complicated, time-consuming involve costly procedures with limited effectiveness. Herein, a nanobiosensor detecting sodium potassium using folic acid-functionalised reduced graphene oxide-modified RNase A gold nanoclusters (FA-rGO-RNase A/AuNCs) based on “turn-off/turn-on” presented. Firstly, facile optimised protocol fabrication A/AuNCs developed. activity protein after formation studied. then loaded onto FA-rGO, which FA-rGO used as potential carrier quencher A/AuNCs. Finally, “turn-on” sensing strategy developed as-synthesised FA-rGO-RNase revealed excellent performance meets sensitivity required both To best our knowledge, this first work done determining exploring application ion sensor. This serves proof-of-concept combining drug delivery, active targeting therapy cancer cells, well biosensing into single platform.