Simultaneous Determination of Selective Drugs, Fluoxetine, Ketoprofen, Oxybutynin and Clonidine in Human Plasma

The separation and determination of a selective drugs as fluoxetine, ketoprofen, Oxybutynin and clonidine (SI) were done in plasma by high-performance liquid chromatography reverse phase. The chromatographic conditions were gradient mobile phase A –Acetonitrile and B-10mM KH2PO buffer PH 3.3, flow rate 1.0 ml/min, column of octadecyle ODS YMC (Japan)3μ (150 mm x 46 mm) with guard column. The extraction method based on the technique used Liquid / Liquid (LLE). The separation number interfered between the drugs and plasma in the mobile phase. The extraction recoveries were 89.1%, 86% and 90% for fluoxetine, ketoprofen and Oxybutynin, respectively. This method permits the simultaneous determination of all these compounds in plasma. Our method is simple and sensitive, based on qualitative and quantitative studies, the coefficient regression was 0.9998 and coefficient of variation was between 0.46% - 0.77% and the limit of detection was between 18 % – 30 %. The limit of quantization under the described conditions was 25, 50, 75 μg/L for ketoprofen, fluoxetine, Oxybutynin, respectively. Consequently, our results showed a very good correlation and they were useful for quality control in the therapeutic drug monitoring and the poisoning control centers and other fields.