The highly toxic nerve agent sarin (o-isopropyl methyl-phosphonofluoridate, GB) has been used in several armed conflicts and terror attacks in recent decades. Due to its inherent high sensitivity, liquid chromatography-mass spectrometry (LC-MS/MS) has the potential to detect ultratrace levels of fluoride-regenerated G and V agents after appropriate chemical derivatization. A new method for the retrospective determination of exposure to sarin was developed. The method is based on sarin regeneration from blood using the fluoride-induced technique followed by derivatization with 2-[(dimethylamino)methyl]phenol (2-DMAMP) and LC-ESI-MS/MS (MRM) analysis. The validated method presents good linear response in the concentration range of 5-1000 pg/mL with a limit of quantitation (LOQ) of 5 pg/mL, 13.8% accuracy, 16.7% precision and a total recovery of 62% ± 9%. This new analytical approach has several advantages over existing GC/GC-MS-based methods in terms of sensitivity, specificity and simplicity, in addition to a short LC-MS cycle time of 12 min. The method was successfully applied in an in vivo experiment for retrospective determination of sarin in a rabbit exposed to 0.1 LD50 sarin (1.5 µg/kg, i.v.). GB-2-DMAMP was easily determined in samples drawn up to 11 days after exposure. The high S/N ratio (500) observed for the GB-2-DMAMP signal in the 11day sample poses the potential for an extended time frame of months for analysis with this new method for the retrospective detection of sarin exposure. To the best of our knowledge, this is the first report on LC-MS/MS trace analysis of regenerated GB from biological matrices.

中文翻译：

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回顾性测定液相色谱-质谱法测定人血中的再生神经毒剂沙林蛋白，并在体内实施。

近几十年来，剧毒的神经毒药沙林（邻异丙基甲基磷酸膦酸酯，GB）已用于数次武装冲突和恐怖袭击中。由于其固有的高灵敏度，液相色谱-质谱法（LC-MS / MS）具有在适当的化学衍生化后检测超痕量氟化物再生G和V剂的潜力。开发了一种追溯测定沙林暴露量的新方法。该方法基于使用氟化物诱导技术从血液中沙林蛋白再生，然后用2-[（（二甲基氨基）甲基]苯酚（2-DMAMP）衍生化和LC-ESI-MS / MS（MRM）分析。经过验证的方法在5-1000 pg / mL的浓度范围内表现出良好的线性响应，定量限（LOQ）为5 pg / mL，准确度为13.8％，为16。精度为7％，总回收率为62％±9％。这种新的分析方法在灵敏度，特异性和简便性方面比现有的基于GC / GC-MS的方法具有多个优势，而且LC-MS的循环时间短至12分钟。该方法已成功用于体内实验，用于追溯测定暴露于0.1 LD50沙林（1.5 µg / kg，静脉注射）的兔子中的沙林。暴露后长达11天的样本中很容易确定GB-2-DMAMP。在11天的样本中观察到的GB-2-DMAMP信号的高信噪比（500）可能导致使用这种新方法回顾性检测沙林暴露的时间延长了数月。据我们所知，这是有关从生物基质中再生的GB进行LC-MS / MS痕量分析的第一份报告。这种新的分析方法在灵敏度，特异性和简便性方面比现有的基于GC / GC-MS的方法具有多个优势，而且LC-MS的循环时间短至12分钟。该方法已成功用于体内实验，用于追溯测定暴露于0.1 LD50沙林（1.5 µg / kg，静脉注射）的兔子中的沙林。暴露后长达11天的样本中很容易确定GB-2-DMAMP。在11天的样本中观察到的GB-2-DMAMP信号的高信噪比（500）可能导致使用这种新方法回顾性检测沙林暴露的时间延长了数月。据我们所知，这是有关从生物基质中再生的GB进行LC-MS / MS痕量分析的第一份报告。这种新的分析方法在灵敏度，特异性和简便性方面比现有的基于GC / GC-MS的方法具有多个优势，而且LC-MS的循环时间短至12分钟。该方法已成功用于体内实验，用于追溯测定暴露于0.1 LD50沙林（1.5 µg / kg，静脉注射）的兔子中的沙林。暴露后长达11天的样本中很容易确定GB-2-DMAMP。在11天的样本中观察到的GB-2-DMAMP信号的高信噪比（500）可能导致使用这种新方法回顾性检测沙林暴露的时间延长了数月。据我们所知，这是有关从生物基质中再生的GB进行LC-MS / MS痕量分析的第一份报告。