High-Performance Liquid Chromatography/Mass Spectrometry of Psychotropic Drugs

采用新建立的毛细管高效液相色谱(HPLC) /快速原子轰击(FAB) -质谱（MS）联用系统，对苯二氮卓类、吩噻嗪类和丁苯酮类3种代表性精神药物进行了分析。用该系统对27种苯二氮卓类药物、17种吩噻嗪类药物和6种丁噻吩类药物进行了鉴定。大多数化合物在正极模式下可检出准分子峰和适当的片段峰，柱上检出限小于10ng。相对于其质谱测量，负模式下的灵敏度比正模式下的灵敏度低两个数量级。研究了用不同的固相萃取筒从人血或尿中提取药物的方法。一般来说，C_<18>的分离筒对苯二氮卓类药物有效，C_2的分离筒对吩噻嗪类或丁苯酮类药物有效。采用该分离方法，并在阳性模式下采用毛细管高效液相色谱/FAB-MS，可在人口服后血清中鉴定出具有代表性的苯二氮卓类或吩噻嗪类药物及其代谢物。建立了以氘标记咪达唑仑为内标，采用FAB-MS选择性离子监测（SIM）法定量分析血清中代表性苯二氮卓类药物咪达唑仑浓度的方法。浓度在2ng/ml ~ 200ng/ml范围内，校准图呈线性关系，重现性好。毛细管HPLC/FAB-MS对所有化合物均为半定量。然而，我们认为在合适的同位素内标下，FAB-MS的SIM可以进行准确的定量。我们还设计了一种简单的紫外毛细管高效液相色谱法测定人血清中某些苯二氮卓类药物的方法。本研究设计的这些分析方法在临床药理学和法医毒理学中被认为是有用的。

We analyzed three representative psychotropic drugs, benzodiazepines, phenothiazines and butyrophenones, by our recently established system of capillary high-performance liquid chromatography (HPLC) /fast atom bombardment (FAB) -mass spectrometry (MS). The authentic compounds of 27 benzodiazepines, 17 phenothiazines and 6 butyrophenones were analyzed by the system. Quasi-molucular peaks along with adequate fragment peaks were detected in the positive mode for most compounds under investigation with the detection limit of less than 10ng on columun. Sensitivity in the nagative mode with respect to its mass spectral measurement was two order of magnitude lower than that in the positive mode.The extraction of the drugs from human blood or urine was studied using various solid-phase extraction cartridges. In general, C_<18> cartridges were effective for the isolation of benzodiazepines, C_2 cartridges for that of phenothiazines or butyrophenones. With this isolation procedure and the capillary HPLC/FAB-MS in the positive mode, some representative benzodiazepines or phenothiazines together with their metabolites could be identified in human sera after oral administration of them.We established a method for quantitative analysis of the concentration of midazolam, one of representative benzodiazepines, in serum by selected ion-monitoring (SIM) of FAB-MS, using deuterium-labeled midazolam as an internal standard. The calibration graph was linear for concentrations between 2ng/ml and 200ng/ml, and reproducibility was good. The capillary HPLC/FAB-MS was semi-quantitative for all compounds under investigation. However, we feel that accurate quantitation can be made by SIM of FAB-MS with a suitable isotopic internal standard. We also devised a simple method for quantitation of some benzodiazepines in human serum by UV monitoring of the capillary HPLC.These analytical methods devised in this study would seen to be useful in clinical pharmacology as well as in forensic toxicology.