A quantitative method to detect human exposure to sulfur and nitrogen mustards via protein adducts.
Sulfur and nitrogen mustards are internationally banned vesicants listed as Schedule 1 chemical agents in the Chemical Weapons Convention. These compounds are highly reactive electrophiles that form stable adducts to a variety of available amino acid residues on proteins upon exposure. We present a quantitative exposure assay that simultaneously measures agent specific protein adducts to cysteine for sulfur mustard (HD) and three nitrogen mustards (HN1, HN2, and HN3). Proteinase K was added to a serum or plasma sample to digest protein adducts and form the target analyte, the blister agent bound to the tripeptide cysteine-proline-phenylalanine (CPF). The mustard adducted-tripeptide was purified by solid phase extraction and analyzed using isotope dilution LC-MS/MS. Product ion structures were identified using high-resolution product ion scan data for HD-CPF, HN1-CPF, HN2-CPF, and HN3-CPF. Thorough matrix comparison, analyte recovery, ruggedness, and stability studies were incorporated during method validation to produce a robust method. The method demonstrated long term-stability, precision (RSD < 15%), and intra- and inter-day accuracies > 85% across the reportable range of 3.00-200 ng/mL for each analyte. Compared to previously published assays, this method quantitates both sulfur and nitrogen mustard exposure biomarkers, requires only 10 μL of sample volume, and can use either a liquid sample or dried sample spot.
['Pantazides|Brooke G|BG|', 'Quiñones-González|Jennifer|J|', 'Rivera Nazario|Danisha M|DM|', 'Crow|Brian S|BS|', 'Perez|Jonas W|JW|', 'Blake|Thomas A|TA|', 'Johnson|Rudolph C|RC|']
D015415:Biomarkers D002851:Chromatography, High Pressure Liquid D003545:Cysteine D004781:Environmental Exposure D006801:Humans D009150:Mustard Compounds D015203:Reproducibility of Results D012709:Serum Albumin D053719:Tandem Mass Spectrometry
Quantitative method Nitrogen mustard Sulfur mustard LC-MS/MS Cysteine adducts Protein biomarker