Development and validation of a HPLC method for the estimation of tizanidine and ibuprofen in bulk and dosage forms

A new method was established for estimation of Tizanidine and Ibuprofen by RP-HPLC method. The chromatographic conditions were successfully developed for the separation of Tizanidine and Ibuprofen by using Intersil ODS C18 column (250×4.6mm) 5.0μm, flow rate was 1.0ml/min, mobile phase ratio was (40:60 v/v) Potassium di hydrogen Phosphate Buffer: Acetonitrile pH 3.2 (pH was adjusted with Ortho-phosphoric acid), detection wavelength was 269nm. The instrument used was Shimadzu HPLC, UV detector 2450, Spinchrom -software version-2. The method shows linearity between the concentration range of 0.6-1.4μg/ml for Tizanidine and 120-280 for Ibuprofen. The % recovery of Tizanidine and Ibuprofen were found to be in the range of 98.0% - 102.0%. As there was no interference due to mobile phase, the method was found to be specific. The method was robust as observed from insignificant variation in the results of analysis by changes in Flow rate and wavelength variation separately and analysis being performed by different analysts.