Synthesis and characterization of succinylcholine-d18 and succinylmonocholine-d3 designed for simultaneous use as internal standards in mass spectrometric analyses
作者:Uta Kuepper、Frank Musshoff、Burkhard Madea
DOI:10.1002/jms.1230
日期:2007.7
Succinylcholine (SUX) is a routinely used yet potentially lethal depolarizing muscle relaxant, the detection of which poses severe problems to the clinical or forensic analyst: within a few minutes after its in vivo administration, SUX is broken down via succinylmonocholine (SMC) to yield the endogenous substances succinic acid and choline. For quantification of SUX and SMC in biological matrices using mass spectrometric detection, appropriate internal standards, i.e. deuterated analogs of the above substances, are indispensable but not commercially available. Internal standards for both substances were hence tailored to fit the analytical needs. The two-step synthesis and subsequent characterization of SUX-d18 and SMC-d3 using a combination of nuclear magnetic resonance (NMR) spectroscopy, fast atom bombardment mass spectroscopy (FAB-MS) and high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) are described. SUX-d18 was synthesized by reacting ethanolamine and iodomethane-d3 in a first quaternization step to choline-d9, which in turn was esterified with succinyldichloride to yield the final product. SMC-d3 was produced by esterification of succinic acid anhydride with dimethylaminoethanol, yielding desmethyl-SMC as intermediate product. The latter was then reacted with iodomethane-d3 to obtain SMC-d3. 1H- and 13C-NMR data support the identity and purity as well as the designated deuteration of both preparations, findings which were further confirmed by FAB-MS as well as HPLC-MS/MS. Owing to a thoughtful design, the obtained substances SUX-d18 and SMC-d3 feature different deuteration patterns at their trimethylamine moieties, and thus finally offer the possibility to simultaneously quantify SUX and SMC in clinical as well as forensic samples using isotope dilution mass spectrometry. Copyright © 2007 John Wiley & Sons, Ltd.
琥珀酰胆碱(SUX)是一种常规使用但具有潜在致命性的去极化肌肉松弛剂,其检测给临床或法医分析人员带来了严重的问题:在体内给药后几分钟内,SUX 会通过琥珀酰胆碱(SMC)分解产生内源性物质琥珀酸和胆碱。要使用质谱检测法对生物基质中的 SUX 和 SMC 进行定量,适当的内部标准物质(即上述物质的氚代类似物)是必不可少的,但市场上却买不到。因此,这两种物质的内部标准都是根据分析需要定制的。本文介绍了采用核磁共振(NMR)光谱、快速原子轰击质谱(FAB-MS)和高效液相色谱/串联质谱(HPLC-MS/MS)相结合的方法,分两步合成 SUX-d18 和 SMC-d3 并对其进行表征的过程。SUX-d18 是通过乙醇胺和碘甲烷-d3 在第一个季铵化步骤中反应生成胆碱-d9,胆碱-d9 又与丁二酸二氯化物酯化生成最终产物。SMC-d3 是通过琥珀酸酐与二甲基氨基乙醇的酯化反应生成的,中间产物为去甲基 SMC。后者再与碘甲烷-d3 反应,得到 SMC-d3。1H-NMR 和 13C-NMR 数据证明了这两种制剂的特性、纯度和指定的氘化度,FAB-MS 和 HPLC-MS/MS 进一步证实了这些结论。由于设计周到,所获得的物质 SUX-d18 和 SMC-d3 的三甲胺分子具有不同的氘代模式,因此最终为使用同位素稀释质谱法同时定量分析临床和法医样本中的 SUX 和 SMC 提供了可能。Copyright © 2007 John Wiley & Sons, Ltd. All Rights Reserved.