title: High performance liquid chromatographic determination of etofibrate and its hydrolysis products.
abstract: High performance liquid chromatographic (HPLC) method is presented for the determination of etofibrate (EF) and its hydrolysis products. The method was based on HPLC separation of EF from its hydrolysis products using cyanopropyl column at ambient temperature with mobile phase consisting of acetonitrile-10 mM potassium dihydrogen phosphate, pH was adjusted to 4.1 using phosphoric acid (50:50, v/v). Quantitation was achieved with UV detection at 221 nm based on peak area. The flow rate was 1.5 ml min(-1). The proposed method was used to investigate the kinetics of acidic hydrolysis process of EF at different temperatures and the apparent pseudo first-order rate constant, half-life and activation energy were calculated. The kinetics of alkaline hydrolysis process of EF using 0.01 M sodium hydroxide at different temperatures cannot be studied as the drug is rapidly hydrolyzed in alkaline medium. The pH-rate profile of hydrolysis of EF in Britton-Robinson buffer solutions within the pH range 2-10 were studied.
authors.affiliation: Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt. ghhadad@hotmail.com
authors.forename: Alaa
authors.initials: A
authors.lastname: el-Gindy
authors.forename: Ghada M
authors.initials: GM
authors.lastname: Hadad
authors.forename: Waleed M M
authors.initials: WM
authors.lastname: Mahmoud
mesh_terms: D002138:Calibration; D002214:Capsules; D002851:Chromatography, High Pressure Liquid; D002995:Clofibric Acid / Q000031:analogs & derivatives* / Q000032:analysis; D003692:Delayed-Action Preparations; D006207:Half-Life; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D000960:Hypolipidemic Agents / Q000032:analysis*; D007202:Indicators and Reagents; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D012015:Reference Standards; D015203:Reproducibility of Results; D012996:Solutions; D013055:Spectrophotometry, Infrared
chemical_list: D002214:Capsules; D003692:Delayed-Action Preparations; D000960:Hypolipidemic Agents; D007202:Indicators and Reagents; D012996:Solutions; C009746:etofibrate; D002995:Clofibric Acid