Development and Validation of RP-HPLC Method for Simultaneous Estimation of Cefpodoxime Proxetil and Dicloxacillin Sodium in Tablets

A simple, accurate, rapid and precise reversed-phase high-performance liquid chromatographic method has been developed and validated for simultaneous determination of cefpodoxime proxetil and dicloxacillin sodium in tablet. The chromatographic separation was carried out on kromasil C-18 analytical column (250x4.6 mm; 5 mu m) with a mixture of acetonitrile: methanol: trifloroacetic acid (0.001%) with pH 6.5 (30: 50: 20, v/v/v) as mobile phase; at a flow rate of 1.0 ml/min. UV detection was performed at 235 nm. The dicloxacillin sodium and cefpodoxime proxetil were eluted at 1.92 and 3.35 min, respectively. The peaks were eluted with better resolution. Calibration plots were linear over the concentration range 0.5-20 mu g/ml for cefpodoxime proxetil (r(2)=0.9996) and 5-50 mu g/ml for dicloxacillin sodium (r(2)=0.9987). The method was validated for accuracy, precision, linearity and specificity. The method was very sensitive with limit of detection 0.0726, 0.3685 mu g/ml and limit of quantification 0.220, 1.116 mu g/ml for cefpodoxime proxetil and dicloxacillin sodium, respectively. The high recovery and low relative standard deviation confirm the suitability of the method for routine determination of cefpodoxime proxetil and dicloxacillin sodium in bulk drug and tablet dosage form.