A rapid evaluation of acute hydrogen sulfide poisoning in blood based on DNA-Cu/Ag nanocluster fluorescence probe.

Hydrogen sulfide (H2S) is a highly toxic gas as a cause of inhalational death. Accurate detection of H2S poisoning concentration is valuable and vital for forensic workers to estimate the cause of death. But so far, it is no uniform and reliable standard method to measure sulfide concentrations in H2S poisoning blood for forensic identification. This study introduces a fluorescence sensing technique into forensic research, in which a DNA-templated copper/silver nanocluster (DNA-Cu/AgNCs) fluorescence probe has been proposed to selective detection of S(2-). Under an optimized condition, the proposed method can allow for determination of S(2-) in the concentration range of 10 pM to 1 mM with a linear equation: y = -0.432 lg[S(2-)] + 0.675 (R(2) = 0.9844), with the limit of detection of 3.75 pM. Moreover, acute H2S poisoning mouse models were established by intraperitoneally injected different doses of Na2S, and the practical feasibility of the proposed fluorescence sensor has been demonstrated by 35 poisoning blood samples. This proposed method is proved to be quite simple and straightforward for the detection of H2S poisoning blood. Also it may provide a basis for sulfide metabolizing study in body, and it would be meaningful to further push forensic toxicology identification and clinical laboratory research.