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

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 x 10(-6) M to 1.0 x 10(-4) M with a detection limit of 1.1 x 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.