同位素稀释气相色谱-质谱联用法监测芥子气染毒家兔尿液中的硫二甘醇

摘要

A sensitive determination method for sulfur mustard ( HD ) metabolites thiodiglycol ( TDG ) in rabbit urine was established and validated using isotope dilution negative ion chemical ionization ( NICI) gas chromatography-mass spectrometry ( GC-MS ) , in which deuterated thiodiglycol ( TDG-d8 ) was used as internal standard. Two solid-phase extraction ( SPE) steps were established and optimized in order to reduce the interfering backgrounds, one was used to extract thiodiglycol ( TDG ) from urine with self-assemblied Florisil SPE cartridges, another cleaning treatment of the by-products after pentafluorobenzoyl chloride (PFBZ) derivatization. The results showed that the limits of detection quantitation of this method were 0. 1 and 0. 3 μg/L, respectively. The exposure time-response relationship and exposure dose-response relationship of TDG in rabbit urine were studied after rabbit skin exposure to sulfur mustard (HD, 0. 02-0. 15 LD50). The TDG levels in the rabbit urine increased rapidly during the first day after application and then decreased over time for all dosage groups. A secondary release was also noted for the high-dose group, and the duration of high TDG excretion levels was correlated positively with the HD dosage levels. We thus concluded that abnormally high levels of TDG in urine could be used as a clear diagnostic indicator of HD exposure.%以硫二甘醇( TDG)的八氘代同位素( TDG-d8)为内标,采用自制Florisil固相萃取( SPE)柱提取尿样中的TDG,用五氟苯甲酰氯( PFBZ)衍生化后,再经SPE净化富集,通过考察优化两步固相萃取( SPE)等前处理步骤,建立了尿液中TDG的高灵敏同位素稀释-负化学电离-气相色谱/质谱( ID-NCI-GC/MS)分析方法。研究了家兔皮肤芥子气(HD)染毒(0.02~0.15 LD50)后,尿液中TDG随时间变化的时效关系及其与HD染毒剂量间的量效关系。结果显示,本方法的检出限为0.1μg/L,定量限为0.3μg/L；家兔染毒后尿液中TDG含量迅速升高,然后又快速减少,并呈现二次释放的特点；各剂量组在第1日内TDG排出量最多,且随着中毒剂量增高,尿液中高含量的TDG维持时间延长。因而,尿液中TDG的异常升高可以作为HD暴露的重要特征指标。