title: Study of the liquid chromatography retention of some fibrate-type antihyperlipidemic drugs on C18 and CN columns: application for quantitation in pharmaceutical formulations.
abstract: The 6 antihyperlipidemic agents-bezafibrate, ciprofibrate, clofibrate, clofibric acid, fenofibrate, and gemfibrozil-were separated on octadecyl (C18) and cyano (CN) chemically bonded columns using mobile phases containing phosphate buffer and different amounts of acetonitrile, dioxane, propan-2-ol, methanol, and tetrahydrofuran. Relationships between log k values and mobile phase composition have been examined for these systems. Analysis was performed on a Waters LC system with Merck LichroCART C18 and CN 125 mm columns using a flow rate of 1 mL/min and 227 nm detection. More than one-half of the results fitted Snyder-Soczewinski equations with r >0.995. Separation of all drugs was achieved on the C18 column with a mobile phase containing 45% propan-2-ol in phosphate buffer (pH = 2.145) and on a CN column with 20% acetonitrile in the same buffer. The best mobile phase, containing 45% propan-2-ol, was used to quantitate bezafibrate, ciprofibrate, fenofibrate, and gemfibrozil in pharmaceutical formulations. The active substances were extracted with methanol. The calibration curve was constructed in the 0.1-0.8 mg/mL range for all drugs and provided satisfactory linearity (Lack-of-Fit test and Mandel's test). The recovery function was sufficiently linear in all cases, with an insignificant intercept and slope very close to 1. Accuracy was tested by quantitating 3 fortified samples (50, 100, and 150%), which gave results without significant differences. None of the excipients interfered in the analysis. The recovery was 99.85% for bezafibrate, 99.02% for ciprofibrate, 99.53% for fenofibrate, and 99.92% for gemfibrozil, with relative standard deviation values of 0.63, 1.61, 1.84, and 0.88%, respectively.
authors.affiliation: Medical University, Department of Medicinal Chemistry, 6 Chodźki St, 20-093 Lublin, Poland.
authors.forename: Genowefa
authors.initials: G
authors.lastname: Misztal
authors.forename: Lukasz
authors.initials: L
authors.lastname: Komsta
mesh_terms: D002138:Calibration; D002214:Capsules; D002626:Chemistry, Pharmaceutical; D002853:Chromatography, Liquid; D000960:Hypolipidemic Agents / Q000032:analysis*; D007202:Indicators and Reagents; D016014:Linear Models; D012015:Reference Standards; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D013607:Tablets
chemical_list: D002214:Capsules; D000960:Hypolipidemic Agents; D007202:Indicators and Reagents; D013607:Tablets