Abstract: AIM: To establish a simple, sensitive method of high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) for the determination of Indapamide in human plasma.METHODS: Repaglinide calcium was used as internal standard.Indapamide was separated on an Agilent-ZORBAX-C₁₈ column (2.1 mm×150 mm,5.0 μm).The mobile phase consisted of acetonitrile-0.1% formic acid(90∶10).Electrospray ionization(ES1) was applied and operated in the positive multiple reaction monitoring(MRM) mode,used the transitions of [M+H]+m/z 388.4 m/z 247.4 and [M+H]+m/z 384.2 m/z 231.3 to quantify Indapamide and the internal standard respectively.RESULTS: The linear calibration curve was obtained over the concentration range of 0.5-50 ng/mL.The limit of quantification was 0.5 ng/mL.The inter- and intra-day precision (RSD) were less than 15%.The average recovery was between 94.60% and 110.33%.CONCLUSION: The method had been proved to be specific,convenient,sensitive and suitable for the clinical investigation of Indapamide pharmacokinetics.

Key words: Indapamide, HPLC-MS-MS, Plasma concentration