title: In vivo metabolism study of polygalic acid in rat using HPLC-ESI-MSn.
abstract: A very simple and direct method has been established for the determination of polygalic acid and its metabolites in rat urine based on HPLC coupled with electrospray ionization multi-stage tandem mass spectrometry (HPLC-ESI-MS(n)). The rats were administered a single dose (100 mg/kg) of polygalic acid by oral gavage. The urine samples were collected and purified through a C(18) solid-phase extraction cartridge, and then these pretreated samples were injected into a reversed-phase C(18) column with a gradient elution program, whereas acetonitrile-0.5% aqueous formic acid was used as mobile phase and detected by an on-line MS/MS system. As a result, the parent drug and its four metabolites were identified and characterized in rat urine for the first time by comparing their changes in molecular mass (ΔM), retention times and full-scan MS(n) spectra with those of the parent drug. A possible metabolic pathway of polygalic acid was investigated and proposed. More importantly, the results demonstrated that the newly developed method (HPLC-ESI-MS(n)) was sensitive, simple and suitable for the determination of polygalic acid and its metabolites in biological samples.
authors: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 501 Haike Road, Zhangjiang, Pudong, Shanghai 201203, People's Republic of China.
authors: Yun
authors: Y
authors: Ling
authors: Bin
authors: B
authors: Wu
authors: Ke
authors: K
authors: Wang
authors: Huihui
authors: H
authors: Liu
authors: Luying
authors: L
authors: Chen
authors: Mingsong
authors: M
authors: Fan
authors: Zhaolin
authors: Z
authors: Sun
authors: Chenggang
authors: C
authors: Huang