High-througput screening and characterization of reative metabolites using polarity switching of hybrid triplequadrapole linear ion trap mass spectrometry
High-througput screening and characterization of reative metabolites using polarity switching of hybrid triplequadrapole linear ion trap mass spectrometry
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DOI：
10.1021/ac702232r
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发表时间：
2008-03-01
影响因子：
7.4
通讯作者：
Zhu, Mingshe
中科院分区：
文献类型：
--
作者：
Wen, Bo;Ma, Li;Zhu, Mingshe
利用负前体离子（PI）作为扫描扫描触发三重四极线性离子阱质谱仪获取正增强产物离子（EPI）光谱，开发了一种高灵敏度和高效的方法来检测和表征谷胱甘肽（γ -谷氨酰半胱氨酸，GSH）捕获的反应性代谢物。负前体离子扫描步骤监测m/z 272处的阴离子，对应于源自谷胱甘肽基部分的去质子化γ -谷氨酰-脱氢丙氨酰-甘氨酸。由于m/z 272处阴离子的独特性和丰度，这种单次调查扫描在检测未知的谷胱甘肽偶联物方面表现出广泛的实用性。通过液相色谱/串联质谱（LC/MS/MS）分析获得的MS2阳性光谱，该光谱具有丰富的片段，没有质量切断，从而实现了进一步的结构表征。通过对乙酰氨基酚、氯氮平、双氯芬酸、丙咪嗪、甲氯芬酸和噻氯匹定等多种模型化合物，对该方法的有效性和可靠性进行了评估。结果，PI-EPI方法揭示了已知加合物的存在，并在许多情况下确定了以前未报道的额外共轭物。与广泛使用的中性损失（NL）扫描分析相比，该方法对不同类型的谷胱甘肽偶联物具有更高的灵敏度和选择性。更重要的是，PI-EPI方法适用于药物发现过程中反应性代谢物的高通量筛选。
A highly sensitive and efficient method has been developed for detection and characterization of glutathione (gamma-glutamyl-cysteinylglycine, GSH)-trapped reactive metabolites using a negative precursor ion (PI) as the survey scan to trigger the acquisition of positive enhanced product ion (EPI) spectra on a triple quadrupole linear ion trap mass spectrometer. The negative precursor ion scan step was carried out monitoring the anion at m/z 272, corresponding to deprotonated gamma-glutamyl-dehydroalanyl-glycine originating from the glutathionyl moiety. Because of the uniqueness and abundance of the anion at m/z 272, this single survey scan exhibited broad utility in the detection of unknown GSH conjugates. Further structural characterization was achieved by analyzing positive MS2 spectra that featured rich fragments without mass cutoff and were acquired in the same liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. The effectiveness and reliability of this approach was evaluated using a number of model compounds in human liver microsomal incubations, including acetaminophen, clozapine, diclofenac, imipramine, meclofenamic acid, and ticlopidine. As a result, the PI-EPI approach revealed the presence of known adducts and, in many instances, identified additional conjugates that had not been reported previously. In comparison to the widely used neutral loss (NL) scanning analysis, this approach provided superior sensitivity and selectivity for different types of GSH conjugates. More importantly, the PI-EPI approach is suitable for high-throughput screening of reactive metabolites in the drug discovery process.