SIMULTANEOUS DETERMINATION OF PHENOBARBITAL AND PHENYTOIN BY USING RP-HPLC METHOD IN PURE AND ITS PHARMACEUTICAL DOSAGE FORM

A rapid and precise reverse phase high performance liquid chromatographic method has been developed for the validated of Phenobarbital and Phenytoin, in its pure form as well as in tablet dosage form. Chromatography was carried out on a Symmetry C18 (4.6 x 150mm, 5µm) column using a mixture of Methanol: Phosphate Buffer pH 3.5 (65:35) as the mobile phase at a flow rate of 1.0ml/min, the detection was carried out at 270 nm. The retention time of the Phenobarbital and Phenytoin was 2.456, 4.312 ±0.02min respectively. The method produce linear responses in the concentration range of 5-25mg/ml of Phenobarbital and 2.5-12.5mg/ml of Phenytoin. The method precision for the determination of assay was below 2.0%RSD. The method is useful in the quality control of bulk and pharmaceutical formulations. Keywords: Phenobarbital, Phenytoin, RP-HPLC, validation