MALDI-TOF质谱法检测人血清中沙林-丁酰胆碱酯酶加合物

Detection of Sarin-Butyrylcholinesterase Adduct in Human Serum by MALDI-TOF Mass Spectrometry

对生物医学样品进行化学毒剂分析检测是禁止化学武器组织(OPCW)核查小组在毒剂指称使用调查中收集事实的方法之一。丁酰胆碱酯酶(BChE)作为有机磷毒剂在体内的作用靶点,是有机磷毒剂染毒检测的最佳生物指示物之一。利用亲和固相萃取(SPE)技术进一步发展了样品预处理方法,建立了血液样品中染毒BChE的分析方法;利用胰蛋白酶酶解方法,采用基质辅助激光解吸/电离飞行时间质谱(MALDI-TOFMS)比较了血液中BChE在沙林染毒前后的肽指纹谱变化。该方法灵敏度高、快速简便,可用于OPCW生物医学样品中毒剂暴露染毒的追溯性检测。

The analysis of biomedical samples is one part of the verification programs of OPCW （Organization for the Prohibition of Chemical Weapons）, and the results would be used as evidence in case of allegations of chemical agents use. The organophosphorus nerve agents could covalently conjugate with human butyrylcholinesterase （BChE）, which is one of the most important biomarkers to verify an exposure to nerve agents. In this paper, the affinity SPE technology was employed as pretreatment method on the case of the detection of serum samples. The difference of peptide mass fingerprints between BChE and sarin- BChE was compared by matrix-assisted laser desorption/ionization time-of-flight mass spec- trometry （MALDI-TOF MS） combined with trypsin digest, and the modified tryptic pep- tide by satin （[M＋H]＋ 3 048. 411 u） was found. The unmodified and modified fragmentswere also verified by tandem mass spectrometry, and the modified site could be attributed to Ser198. The method of verification of human plasma exposure to sarin can be used to track other organophosphorus agents successfully.