title: Analysis of pharmaceutical dosage forms for oxfendazole: I. Reverse phase liquid chromatographic determination of oxfendazole in swine premix.
abstract: A reverse phase liquid chromatographic (LC) procedure is described for quantitating oxfendazole (2-(methoxycarbonylamino)-5-phenylsulfinylbenzimidazole] in swine premix. Sample preparation consists of extracting oxfendazole with an acetone-methanol mixture. An aliquot of the extract is then centrifuged to separate undissolved premix excipients. Internal standard is added to the supernate and the sample is further diluted with water-acetonitrile-phosphoric acid (80 + 20 + 1). Oxfendazole is quantitatively determined using a Partisil-5-ODS-3 column with acetonitrile-0.01 M phosphate buffer (pH 6.0) as the mobile phase. The method is stability specific and yields a mean recovery of 101.1 +/- 0.4% for the 1.35% premix formulation. The dependence of chromatographic performance characteristics on mobile phase organic content, pH, and buffer concentration is also reported.
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D000871:Anthelmintics / Q000032:analysis*; D001562:Benzimidazoles / Q000032:analysis*; D002021:Buffers; D002853:Chromatography, Liquid; D004355:Drug Stability; D006863:Hydrogen-Ion Concentration; D012997:Solvents; D013552:Swine
chemical_list: D000871:Anthelmintics; D001562:Benzimidazoles; D002021:Buffers; D012997:Solvents; C011030:oxfendazole