Authors: Elena Gabriela Oltean, A. Nica Affiliation: Romvac Company SA, Bucuresti
An isocratic high–performance liquid chromatography (HPLC) procedure was developed for quantitative determination of albendazole in suspensions dosage forms of Rombendazol, HPLC separation was carried out by reversed phase chromatography KROMASIL C18 (150 mmx4.6 mm i.e.; 5 ìm particle size), held at 25°C. The mobile phase consisted of Methanol/Distilled Water (65/35 v/v), run at flow rate of 1.2 mL/ min and with UV detection at 308 nm. Method validation investigated parameters such as linearity (r2=0.9999), range, precision, accuracy, specificity, limit of detection and limit of quantification. The described method can be successfully applied for the analysis of suspensions dosage forms.
Authors: Ana Csuma, Ana Cismileanu Affiliation: S.N. Institutul Pasteur S.A., Bucuresti
Treating the animals with veterinary medicines raise the issue of residues that can persist in their edible tissues. In order to establish the withdrawal time necessary for depletion of the residues to sufficiently low concentration not to affect human health, biological tests performed on animals implicitly involve the use of sensitive and reliable analytical methods for residues determination. The aim of this work was to establish and validate a sensitive and reliable method for simultaneous determination of albendazole and its metabolites, albendazole sulfoxide, albendazole sulfone and 2-aminoalbendazole sulfone in animal tissues by LC/MS/MS. The method involves acid hydrolysis with 6N HCl in order to release most residues, in particular the bound metabolite 2-amino-albendazole sulfone especially from liver, followed by extraction with ethyl acetate and solid phase clean up of the extract on a C18 SPE cartridge. The liquid chromatographic separation was achieved on a XTerra MS C18 column (10 cm x 2,1 mm, 3,5 ìm), with gradient elution of 0,1% formic acid – methanol. Detection was performed by mass spectrometry in ESI+ mode. The limits of quantification were lower than 4 ìg/ml for each component.The correlation coefficients (R2) of the calibration curves (in the range from 0,01 ìg/ml to 0,5 ìg/ml) were higher then 0,9935. The relative standard deviations of repetability on samples naturaly contaminated from treated animals were between 5,75% and 11,6%. Recoveries from fortified muscles in the range of 10 ìg/kg to 100 ìg/kg were between 70,2% and 88% with relative standard deviation of 5,4% – 12,2%. For liver fortified in the range of 100 ìg/kg to 1000 ìg/kg recoveries between 70,3% and 83,2% were obtained with relative standard deviation of 5,7 %-11%.