title: Simple fluorimetric liquid chromatographic method for the analysis of undecylenic acid and zinc undecylenate in pharmaceutical preparations.
abstract: A simple and selective liquid chromatographic method is described for the analysis of undecylenic acid (UA) and zinc undecylenate (ZnUA) in pharmaceutical preparations. The method is based on the derivatization of the analytes extracted from various samples with 2-(2-naphthoxy)ethyl 2-(piperidino)ethanesulfonate. The resulting derivative was analyzed by liquid chromatography with fluorimetric detection. The quantitation of the method is in the range of 3.0-50.0 microM UA with a detection limit of about 0.3 microM (S/N = 3 with 10 microl injection). We found that acetonitrile is a selective solvent for differentially dissolving UA from coexisted ZnUA in compound formulation. This results in the specific analysis of UA in the presence of ZnUA and simply analyzing the coexisted ZnUA by the value of total UA (UA+ZnUA) minus that of UA. Application of the method to the analysis of undecylenic acid and zinc undecylenate in ointment, powder and solution preparations proved feasible.
authors.affiliation: Graduate Institute of Pharmaceutical Sciences, College of Pharmacy, Kaohsiung Medical University, Taiwan.
authors.forename: Ming-Chun
authors.initials: MC
authors.lastname: Lin
authors.forename: Hsin-Lung
authors.initials: HL
authors.lastname: Wu
authors.forename: Hwang-Shang
authors.initials: HS
authors.lastname: Kou
authors.forename: Shou-Mei
authors.initials: SM
authors.lastname: Wu
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D005470:Fluorometry; D009824:Ointments / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D011208:Powders / Q000737:chemistry; D014476:Undecylenic Acids / Q000032:analysis*; D015032:Zinc / Q000032:analysis
chemical_list: D009824:Ointments; D004364:Pharmaceutical Preparations; D011208:Powders; D014476:Undecylenic Acids; D015032:Zinc