Forensic analysis of hydrogen sulfide poisoning cases: Innovative LC-MS/MS methodology for accurate detection in human blood

Abstract

Identification of hydrogen sulfide poisoning cases has long been a challenging issue in the field of forensic science. Due to the relatively limited histopathological features associated with hydrogen sulfide poisoning, traditional anatomy faces difficulties in accurately determining such cases. Additionally, existing detection methods have inherent limitations, including complex analytical processes and low sensitivity. This research uses the principle of the reaction between triazine and hydrogen sulfide to generate thiadiazine to measure hydrogen sulfide levels in the blood, applying this method to practical case examinations. A 0.2 mL blood sample is taken and diluted with 0.8 mL saturated borax solution. In a test tube, 1 mL acetonitrile solution containing 0.1 % formic acid is taken, followed by the sequential addition of 0.1 mL diluted solution and 0.1 mL 1 % triazine aqueous solution. After thorough mixing, the mixture is allowed to stand for 30 min, during which hydrogen sulfide undergoes a derivative reaction with triazine, producing thiazine. Subsequently, the sample undergoes centrifugation and membrane filtration, and the resulting solution is analyzed using Liquid Chromatograph Mass Spectrometer. The results reveal a strong linear relationship of hydrogen sulfide within the concentration range of 10 to 2000 ng/mL, with an R2 of 0.9989. The detection limit is 3 ng/mL, and the quantification limit is 10 ng/mL. In six cases of hydrogen sulfide poisoning, the presence of hydrogen sulfide in the blood of all deceased individuals is detected, with concentrations ranging from 0.25 to 0.79 μg/mL. For the first time, this study establishes an LC-MS/MS method for determining hydrogen sulfide in blood, meeting the detection requirements for hydrogen sulfide poisoning cases.