A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 an...A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 and simvastatin d6 were used as internal standards for ezetimibe and simvastatin, respectively. MS/MS detection involved a switch of electron spray ionization mode from negative to positive at retention time 3.01 rain. Samples were extracted from plasma by liquid-liquid extraction using tertiary butyl methyl ether. Chromatographic separation was achieved with Agilent Eclipse XBD-CIs column using mobile phase that consisted of a mixture of ammonium acetate （pH4.5; 10 mM）-acetonitrile （25：75 v/v）. The method was linear and validated over the concentration range of 0.2--40.0 ng/rnL for simvastatin and 0.05-15.0 ng/mL for ezetimibe. The transitions selected were m/z 408.3→271.1 and m/z 412.0→275.10 for ezetimibe and ezetimibe d4, and m/z 419.30 → 285.20 and rrdz 425.40 →199.20 for simvastatin and simvastatin d6. Intra- and inter-batch precisions for ezetimibe were 1.6-14.8% and 2.1-13.4%; and for simvastatin 0.94-9.56% and 0.79-12%, respectively. The proposed method was sensitive, selective, precise and accurate for the quantification of ezetimibe and simvastatin simultaneously in rat plasma. The method was successfully applied to a pharmacokinetic study by oral co-administration of ezetimibe and simvastatin in SD rats.展开更多
A sensitive and reliable liquid chromatography-electrospray ionisation-tandem mass spectrometry(LC-ESI-MS/MS)method was established to simultaneously quantitate four categories of compounds(isoflavonoids,flavonoids,al...A sensitive and reliable liquid chromatography-electrospray ionisation-tandem mass spectrometry(LC-ESI-MS/MS)method was established to simultaneously quantitate four categories of compounds(isoflavonoids,flavonoids,alkaloids and saponins)in Gegen-Qinlian decoction(GQD).These compounds were separated by a Shiseido CAPCELL PAK C18 column with a linear gradient consisting of 0.1%(v/v)formic acid in water(A)and 0.1%(v/v)formic acid in acetonitrile(B),and delivered at a flow rate of 0.3 mL/min.All the analytes were determined by electrospray positive ionization tandem mass spectrometry in a multiple reaction monitoring(MRM)mode.Linearity,accuracy,precision,recovery and stability of the method were evaluated with the validation over the range of 4.0-538 5 ng/mL.The proposed method was applied to the analysis of a Chinese herbal preparation GQD successfully.展开更多
文摘A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed for simultaneous quantification of ezetimibe and simvastatin in rat plasma. The deuterium isotopes： ezetimibe d4 and simvastatin d6 were used as internal standards for ezetimibe and simvastatin, respectively. MS/MS detection involved a switch of electron spray ionization mode from negative to positive at retention time 3.01 rain. Samples were extracted from plasma by liquid-liquid extraction using tertiary butyl methyl ether. Chromatographic separation was achieved with Agilent Eclipse XBD-CIs column using mobile phase that consisted of a mixture of ammonium acetate （pH4.5; 10 mM）-acetonitrile （25：75 v/v）. The method was linear and validated over the concentration range of 0.2--40.0 ng/rnL for simvastatin and 0.05-15.0 ng/mL for ezetimibe. The transitions selected were m/z 408.3→271.1 and m/z 412.0→275.10 for ezetimibe and ezetimibe d4, and m/z 419.30 → 285.20 and rrdz 425.40 →199.20 for simvastatin and simvastatin d6. Intra- and inter-batch precisions for ezetimibe were 1.6-14.8% and 2.1-13.4%; and for simvastatin 0.94-9.56% and 0.79-12%, respectively. The proposed method was sensitive, selective, precise and accurate for the quantification of ezetimibe and simvastatin simultaneously in rat plasma. The method was successfully applied to a pharmacokinetic study by oral co-administration of ezetimibe and simvastatin in SD rats.
基金supported by the National Natural Science Foundation of China(No.90202039)"Chen Guang" Project for Personnel Cultivation of Shanghai Municipal Education Commission(No.09CG43)the Construction Program for Innovative Research Teamin Shanghai Institutions of Higher Education
文摘A sensitive and reliable liquid chromatography-electrospray ionisation-tandem mass spectrometry(LC-ESI-MS/MS)method was established to simultaneously quantitate four categories of compounds(isoflavonoids,flavonoids,alkaloids and saponins)in Gegen-Qinlian decoction(GQD).These compounds were separated by a Shiseido CAPCELL PAK C18 column with a linear gradient consisting of 0.1%(v/v)formic acid in water(A)and 0.1%(v/v)formic acid in acetonitrile(B),and delivered at a flow rate of 0.3 mL/min.All the analytes were determined by electrospray positive ionization tandem mass spectrometry in a multiple reaction monitoring(MRM)mode.Linearity,accuracy,precision,recovery and stability of the method were evaluated with the validation over the range of 4.0-538 5 ng/mL.The proposed method was applied to the analysis of a Chinese herbal preparation GQD successfully.
