采用液相色谱/电喷雾串联质谱联用技术结合在线氘代实验对莫西沙星进行体内代谢研究。

In vivo metabolic investigation of moxifloxacin using liquid chromatography/electrospray ionization tandem mass spectrometry in combination with online hydrogen/deuterium exchange experiments.

机构信息

National Centre for Mass Spectrometry, Indian Institute of Chemical Technology, Hyderabad, 500 007, India.

出版信息

Rapid Commun Mass Spectrom. 2012 Aug 30;26(16):1817-31. doi: 10.1002/rcm.6288.

DOI:10.1002/rcm.6288

PMID:22777784

Abstract

RATIONALE

Tuberculosis is a leading cause of death from an infectious disease and moxifloxacin is an effective drug as compared to other fluoroquinolones. To date only two metabolites of the drug are known. Therefore, the present study on characterization of hitherto unknown in vivo metabolites of moxifloxacin using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) is undertaken.

METHODS

In vivo metabolites of moxifloxacin have been identified and characterized by using LC/ESI-MS/MS in combination with an online hydrogen/deuterium (H/D) exchange technique. To identify in vivo metabolites, blood, urine and faeces samples were collected after oral administration of moxifloxacin to Sprague-Dawley rats. The samples were prepared using an optimized sample preparation approach involving protein precipitation, liquid-liquid extraction followed by solid-phase extraction and LC/MS/MS analysis.

RESULTS

A total of nine phase I and ten phase II metabolites of moxifloxacin have been identified in urine samples including N-sulphated, glucuronide and hydroxylated metabolites which are also observed in plasma samples. In faeces samples, only the N-sulphated metabolite is observed. The structures of metabolites have been elucidated based on fragmentation patterns, accurate mass measurements and online H/D exchange LC/MS/MS experiments. Online H/D exchange experiments are used to support the identification and structural characterization of drug metabolites.

CONCLUSIONS

A total of 19 in vivo metabolites of moxifloxacin have been characterized using LC/ESI-MS/MS in combination with accurate mass measurements and online H/D exchange experiments. The main phase I metabolites of moxifloxacin are hydroxylated, decarbonylated, desmethylated and desmethylhydroxylated metabolites which undergo subsequent phase II glucuronidation pathways.

摘要

背景

结核病是传染病死亡的主要原因，莫西沙星作为一种有效的药物，优于其他氟喹诺酮类药物。迄今为止，仅已知该药物的两种代谢物。因此，本研究采用液相色谱/电喷雾串联质谱法（LC/ESI-MS/MS）对莫西沙星体内未知的代谢物进行了特征描述。

方法

采用 LC/ESI-MS/MS 结合在线氘代（H/D）交换技术，对莫西沙星的体内代谢物进行了鉴定和特征描述。为了鉴定体内代谢物，在 Sprague-Dawley 大鼠口服莫西沙星后，采集了血液、尿液和粪便样本。采用优化的样品制备方法，包括蛋白质沉淀、液液萃取和固相萃取，对样品进行了制备，然后进行 LC/MS/MS 分析。

结果

在尿液样品中，共鉴定出 9 种 I 相代谢物和 10 种 II 相代谢物，包括磺化、葡萄糖醛酸化和羟化代谢物，这些代谢物也在血浆样品中被观察到。在粪便样品中，仅观察到 N-磺化代谢物。根据碎片模式、精确质量测量和在线 H/D 交换 LC/MS/MS 实验，推断出代谢物的结构。在线 H/D 交换实验用于支持药物代谢物的鉴定和结构特征描述。