A novel “Off-On” fluorescent probe based on carbon nitride nanoribbons for the detection of citrate anion and live cell imaging

Abstract

A novel fluorescent “off-on” probe based on carbon nitride (C3 N4) nanoribbons was developed for citrate anion (C6 H5 O73−) detection. The fluorescence of C3 N4 nanoribbons can be quenched by Cu2+ and then recovered by the addition of C6 H5 O73−, because the chelation between C6 H5 O73− and Cu2+ blocks the electron transfer between Cu2+ and C3 N4 nanoribbons. The turn-on fluorescent sensor using this fluorescent “off-on” probe can detect C6 H5 O73− rapidly and selectively, showing a wide detection linear range (1~400 µM) and a low detection limit (0.78 µM) in aqueous solutions. Importantly, this C3 N4 nanoribbon-based “off-on” probe exhibits good biocompatibility and can be used as fluorescent visualizer for exogenous C6 H5 O73− in HeLa cells.