Simultaneous Quantification of Biomarkers for Bis-(2-chloroethyl) Sulfide and 1,2-Bis(2-chloroethylthio) Ethane Exposure in Human Urine at Trace Exposure Levels by Gas Chromatography Tandem Mass Spectrometry via Simultaneous Incubation and Extraction.

Sulfur mustard [HD; bis-(2-chloroethyl) sulfide] and other analogues are a kind of highly toxic vesicant and have been prohibited by the Organization for the Prohibition of Chemical Weapons (OPCW) since 1997. Exposures to HD could generate several adducts in the plasma and hydrolysis products in the urine, which are widely applied as biomarkers to identify HD exposure in forensic analysis. Several methods have been developed for the detection of related biomarkers. However, most methods are based on complex derivatization, and not enough attention is paid to HD analogues. A modified and convenient analytical method reported herein includes simultaneous incubation and organic solvent extraction. The biomarkers such as thiodiglycol and 1,2-bis (2-hydroxyethylthio) are transferred to HD and 1,2-bis(2-chloroethylthio) ethane via hydrochloric acid at the appropriate temperature. The analytes are analyzed by gas chromatography tandem mass spectrometry (GC-MS/MS) with 2-chloroethyl ethyl sulfide (2-CEES) applied as the internal standard. The interday and intraday study according to FDA rules has been achieved to evaluate the accuracy and precision of the method. The two targets are detected with a good linearity (R2 > 0.99) in the concentration ranges from 5 to 1000 ng/mL and 10 to 1000 ng/mL, with small relative standard deviations (RSD ≤6.62% and RSD ≤6.93%) and favorable recoveries between 90.3 and 107.3% and between 89.4 and 108.7%, respectively. The established method can be used for retrospective detection of sulfur mustards in biological samples and successfully applied in the biomedical proficiency testing organized by the OPCW.

Fluoride derivatization-enabled sensitive and simultaneous detection of biomarkers for nitrogen mustard in human plasma and urine via gas chromatography tandem mass spectrometry.

Methyl-diethanolamine (CAS: 105-59-9), ethyl-diethanolamine (CAS: 139-87-7), and triethanolamine (CAS: 102-71-6) were identified as the degradation products and bio-markers of nitrogen mustard exposure. Sensitive and convenient detection methods for amino alcohol are of great importance to identify nitrogen mustard exposure in forensic analysis. Herein, analytical methods including gas chromatography-tandem mass spectrometry combined with heptafluorobutyryl derivatization and solid phase extraction were established for retrospective detection of the biomarkers in human plasma and urine samples. The efficiency of the method was improved by optimizing the conditions for sample preparation and the GC-MS/MS method. The optimization included the derivatization temperature, reaction time, reagent dosage and solid phase extraction cartridges, eluent and pH of the loading sample. The results indicated that the SCX cartridge resulted in better enrichment and purification effects, and the best recovery could be obtained with pH = 3-4 for the loading samples and an eluent of 2 mL 10% NH4OH/MeOH. The GC-MS/MS parameters were also optimized for better specificity and sensitivity. The established method was fully validated for each analyte both in plasma and urine matrixes. The linear range of analytes in plasma was 1.0-1000 ng mL-1 with a correlation parameter (R2) of ≥0.994, intra-day/inter-day accuracy of 93.7-117%, and relative standard deviation (RSD) of ≤6.5%. Meanwhile the results in urine were 1.0-1000 ng mL-1 with R2 of ≥0.996, intra-day/inter-day accuracy of 94.3-122%, and RSD of ≤6.6%. The detection limit of the analytes was 1.0 ng mL-1. The method was applied for the detection and identification of trace amino alcohols present in urine samples dispatched by the Organization for the Prohibition of Chemical Weapons (OPCW) and the results were confirmed to be correct.