Alexandru Robert Vlad, Gabriel Hancu, Hajnal Kelemen, Diana Ciurcă and Amelia Tero-Vescan
Sibutramine is a chiral anti-obesity drug which decreases food intake and increases energy expenditure. In therapy it is used as a racemic mixture; however both pharmacokinetic and pharmacodynamic data have revealed enantioselective behavior of sibutramine and its major active metabolites. Several chromatographic and electrophoretic analytical methods have been published so far for the chiral determination of sibutramine from pharmaceutical preparations and biological samples. The current paper aims to provide a systematic review of the stereochemical aspects and analytical methods used for the enantiodetermination of sibutramine and its active enantiomers covering the last 15 years.
Adriana Modroiu, Gabriel Hancu, Robert Alexandru Vlad, Ștefana Stăcescu, Ruxandra Soare and Hajnal Kelemen
A rapid, simple and sensitive capillary zone electrophoresis method was developed for the simultaneous determination of amlodipine besylate and telmisartan, in fixed-dose combinations, through the utilization of a UV photodiode array detector. Electrophoretic parameters such as buffer concentration and pH, system temperature, applied voltage and injection parameters, were optimized in order to improve the efficiency of the separation. The best results were obtained when employing fused silica capillary (48 cm length X 50 μm ID) and 50 mM phosphate buffer electrolyte at pH 4.50, + 25 kV applied voltage, as well as 25°C system temperature. The separation was achieved in approximately 3 minutes, with a resolution of 4.90, while the order of migration was amlodipine followed by telmisartan. The analytical performance of the method was verified with regard to linearity, precision and robustness. In addition, the limit of detection and the quantification were calculated.