Blue-emitting glutathione-capped copper nanoclusters as fluorescent probes for the highly specific biosensing of furazolidone

In the present study, the fluorescence sensor based on the GSH-Cu NCs for the determination of furazolidone is developed for the first time. [Display omitted] •In the present study, the fluorescence sensor for the determination of furazolidone is developed for the first time.•Quenching mechanism of fluorescence is due to the inner filter effect and static quenching.•Ultrasensitive and selective determination are achieved for sensing furazolidone.•The limit of detection of furazolidone is 0.012 μM. Herein, a facile, straightforward and green method was developed to prepare copper nanoclusters by using glutathione (GSH) as the protecting agent and ascorbic acid as the reducing agent. The glutathione-templated copper nanoclusters (GSH-Cu NCs) were characterized through fluorescence spectroscopy, UV–vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and fluorescence lifetime analysis. The as-synthesized Cu NCs showed blue fluorescence with a peak centered at 426 nm. The Cu NCs had excellent water solubility, stability and dispersibility. Based on the inner filter effect and static quenching mechanism, Cu NCs were employed to detect furazolidone in bovine serum samples. Under optimal detection conditions, a good linear relationship was observed between F0/F and the furazolidone concentration from 0.05 to 60 μM. The detection limit (LOD) was 0.012 μM. Furthermore, the fluorescence probe was successfully used in the quantification of furazolidone in bovine serum samples. In addition, this analytical method provides a rapid, easy and ultrasensitive fluorescence platform for the detection of furazolidone.