title: High-performance liquid chromatography-mass spectrometric analysis of ramipril and its active metabolite ramiprilat in human serum: application to a pharmacokinetic study in the Chinese volunteers.
abstract: This study presents a rapid, specific and sensitive LC-MS/MS assay for the determination of ramipril and ramiprilat in human serum using enalapril as an internal standard (IS). A Waters Atlantis C18 column (2.1 mm x 100 mm, 3 microm) and a mobile phase consisting of 0.1% formic acid-methanol (25:75, v/v) were used for separation. The analysis was performed by the selected reaction monitoring (SRM) method, and the peak areas of the m/z 417.3-->234.3 and m/z 389.3-->206.2 transition for ramipril and ramiprilat, respectively, were measured versus that of the m/z 377.3-->234.2 for IS to generate the standard curves. The assay linearities of ramipril and ramiprilat were confirmed over the range 0.10-100 ngml(-1) and 0.25-100 ngml(-1), respectively, and limits of quantitation for them were 0.10 and 0.25 ngml(-1), respectively. The linear ranges correspond well with the serum concentrations of the analytes obtained in clinical pharmacokinetic studies. Intraday and interday relative standard deviations of ramipril and ramiprilat were 2.8-6.4% and 4.3-4.6%, 4.4-6.7% and 3.5-4.7%, respectively. The recoveries of ramipril and ramiprilat from serum were in the range of 81.0-98.2%. The developed LC-MS procedures were applied for the determination of the pharmacokinetic parameters of ramipril and ramiprilat following a single oral administration of 10mg ramipril tablets in 18 Chinese healthy male volunteers.
authors.affiliation: The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, PR China. lxy00711@yahoo.com.cn
authors.forename: Xiao-Yang
authors.initials: XY
authors.lastname: Lu
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Shen-Tu
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
mesh_terms: D000284:Administration, Oral; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D002681:China; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D005561:Formates; D006801:Humans; D008297:Male; D000432:Methanol; D011358:Product Surveillance, Postmarketing; D017257:Ramipril / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D013696:Temperature
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D005561:Formates; C030544:formic acid; C052549:ramiprilat; D017257:Ramipril; D000432:Methanol