[Rapid Analysis of Cyanide Based on a Ratiometric Fluorescent Probe Using Gold Nanoclusters-Fluorescein].

OBJECTIVES

To establish a rapid analysis method for cyanide based on a ratiometric fluorescent probe, providing a quantitative strategy for on-site visual and rapid detection of cyanide.

METHODS

A dual-emission ratiometric fluorescent probe (AuNCs-FL) was constructed by using bovine serum albumin (BSA)-stabilized gold nanoclusters (AuNCs, fluorescence emission at 660 nm) as the responsive signal unit and fluorescein (FL, emission at 515 nm) as the internal reference.

RESULTS

The etching effect of cyanide on AuNCs resulted in fluorescence quenching at 660 nm, while the fluorescence intensity of FL at 515 nm remained unchanged, enabling a rapid response analysis of cyanide shift from red to green fluorescence. The developed probe enabled rapid analysis of cyanide within 3 min, with a limit of detection (LOD) of 3.4 mg/L and a visual detection range of 10-100 mg/L.

CONCLUSIONS

The AuNCs-FL fluorescent probe is structurally simple, low-cost, and easy to operate, delivering rapid and accurate results. It also avoids the interference from sulfides encountered in commercial cyanide test kits, making it suitable for the on-site rapid detection of suspected powder samples in cyanide poisoning cases.