A lysozyme-stabilized silver nanocluster fluorescent probe for the detection of sulfide ions

Abstract

Red-emitting lysozyme-stabilized silver nanoclusters (Lys-Ag NCs) were synthesized and utilized as a fluorescent probe for sensing sulfide ions (S²⁻) based on fluorescence quenching. Hence a new method for the detection of S²⁻ was developed. Under optimized experimental conditions, the probe exhibited a stable response for S²⁻ over a concentration range from 5.0 × 10⁻⁶ M to 1.0 × 10⁻⁴ M with a detection limit of 1.1 × 10⁻⁶ M. The feasibility of the proposed method was further demonstrated through the detection of S²⁻ in real samples. The results showed satisfactory recoveries in the range of 97.0–101.4%. Meanwhile, the possible sensing mechanism for the detection of S²⁻ was also discussed. The proposed method for the detection of S²⁻ has potential application in the environmental pollutant analysis.