Abstracto

A validated reversed phase HPLC assay for the determination of cetirizine in human plasma

Reem Al-Swayeh, Syed N.Alvi, Muhammad M.Hammami

A simple and precise reversed-phase high performance liquid chromatography (HPLC) method for the determination of cetirizine in human plasma was developed and validated. Using omeprazole as an internal standard (IS), separation was achieved on Symmetry C18 column. Themobile phase, 10 mM monobasic potassium phosphate and acetonitrile (70:30, v:v) was delivered at a flow rate of 1.2 ml/min. The eluent was monitored spectrophotometricly at 230 nm. Plasma sampleswere deproteinized using a mixture of dichloromethane and hexane (75:25, v:v) and extracts were evaporated and reconstituted in mobile phase. No interference in blank plasma or of commonly used drugs was observed. The relationship between the concentration of cetirizine in plasma and peak area ratio of cetirizine to the ISwas linear over the range of 0.04-2.0 µg/ml. The intra-day and inter-day coefficients of variation and bias were < 8.0 % and < 8.6 %, and <4.5%and <13.5%, respectively. The extraction recovery of cetirizine and the IS from plasma samples was 91%. The method was applied to assess the stability of cetirizine under various conditions generally encountered in the clinical laboratory. Cetirizine in plasma was stable for at least 24 hr at RT, 7 weeks at -20 ºC; and after three freeze-thaw cycles. Cetirizine in processed samples was stable for at least 24 hr at RT or 48 hr at -20 ºC. Stock solution of cetirizine (0.1 µg/ml) in methanol was stable for 24 hr at RT or 7 weeks at -20 ºC.