HPLC Analysis of Benzimidazoles Using Core-shell Columns I

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of biophysics and physical chemistry Candidate: Kateřina Oslejová Supervisor: ing. Vladimír Kubíček, CSc. Title of diploma thesis: HPLC Analysis of Benzimidazoles Using Core-shell Columns I The aim of this work was to transfer the HPLC method of determination of flubendazole and its metabolite, i.e. reduced flubendazole, from a classical C18 column (250×3,0 mm; 5 µm) to core-shell column Ascentis® Express C18 (10×3,0; 2,7 µm) and to find a suitable internal standard. Experiments were performed using liquid chromatograph Agilent 1200 Series® with both DAD and fluorescence detection. Flubendazole was detected with the DAD detector. Low concentrations of reduced flubendazole were detected with the fluorimetric detector. Several mobile phase compositions were tested. The mobile phase consisting of phosphate buffer (pH = 3,0; 0,025 mol/l) and acetonitrile (70/30, v/v) appeared to be a good choice for the separation under study. Two internal standards were exploited for the quantification, depending on the detection principle. Mebendazole served as the internal standard in the case of DAD detection, while oxibendazole was utilized for fluorimetric detection. The proposed method was successfully applied for analyses of real samples