Simultaneous determination of quinapril and its active metabolite quinaprilat in human plasma using high-performance liquid chromatography with ultraviolet detection

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Vol. 766; no. 2; pp. 199 - 207
• Main Authors: Abbara, Ch, Aymard, G, Hinh, S, Diquet, B
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 25.01.2002
• Subjects: Angiotensin-Converting Enzyme Inhibitors - blood; Angiotensin-Converting Enzyme Inhibitors - pharmacokinetics; Calibration; Chromatography, High Pressure Liquid - methods; Humans; Isoquinolines - blood; Isoquinolines - pharmacokinetics; Quinapril; Quinaprilat; Reproducibility of Results; Sensitivity and Specificity; Spectrophotometry, Ultraviolet - methods; Tetrahydroisoquinolines; Therapeutic Equivalency; Quinapril; Quinaprilat
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/S0378-4347(01)00474-1

A high-performance liquid chromatography (HPLC) procedure for the simultaneous determination of quinapril and its active metabolite quinaprilat in human plasma samples is described. A one-step solid-phase extraction (SPE) with C 18 cartridges was coupled with a reversed-phase HPLC system. The system requires two mobile phases composed of tetrabutyl ammonium hydrogensulfate (10 m M adjusted to pH 7)–acetonitrile (62:38, v/v) for quinapril, and (25:75, v/v) for quinaprilat elution through a C 18 Symmetry column and detection at a wavelength of 215 nm. Calibration curves were linear over the ranges 20 to 1000 ng/ml for quinaprilat and 10 to 500 for quinapril. The limits of quantification were 20 and 10 ng/ml for quinaprilat and quinapril, respectively. Extraction recoveries were higher than 90% for quinapril and 80% for quinaprilat. This method has been successfully applied to a bioequivalence study of quinapril in healthy subjects.