Reverse Phase High Performance Liquid Chromatographic Method for the Simultaneous Estimation of Amoxicillin Trihydrate and Tinidazole in the Tablet Dosage Form

A simple, rapid and selective RP -HPLC method has been developed for determination of Amoxicillin trihydrate and Tinidazole in the pharmaceutical dosage form. The chromatographic separation was achieved with reverse phase phenomenex ® (Luna 5μ C18(2) 100A (250 × 4.60 mm) Column in isocratic mode and mobile phase containing 25mM Potassium dihydrogen phosphate (adjusted to pH 4.5 by Ortho-phosphoric acid) and Acetonitrile in the ratio of 40:60 % v/v. The flow rate was 1mL min-1 and effluent was monitored at 238 nm. Retention time was found to be 2.053 min for Amoxicillin trihydrate and 2.944 min for Tinidazole , respectively. Linear regression analysis data for the calibration plot showed that there was good linear relationship between response and concentration in the range of 5-50 μg/ml for both Amoxicillin trihydrate and Tinidazole , respectively. Percentage recoveries obtained for Amoxicillin trihydrate and Tinidazole were 100.87% and 99.52% respectively. The proposed method is precise, accurate, selective and rapid for the simultaneous determination of Amoxicillin trihydrate and Tinidazole in pharmaceutical dosage forms.