Abstract
A simple, specific and accurate isocratic RP-HPLC-DAD method was developed for the simultaneous determination of phenylephrine, paracetamol, caffeine and chlorpheniramine in bulk and tablet dosage form. The four contents are present in variable concentrations and have variable chromatographic behavior making the process of analysis very difficult. For present studies a reversed-phase C-18 column (150mm×4.5mm i.d., particle size 5μm) with mobile phase consisting of acetonitrile, methanol and 10Mm phosphate buffer 16:22:62 (v/v) (pH of buffer 2.5±0.02, adjusted with ortho phosphoric acid) was used. The flow rate was 1.0ml/min and eluents were monitored at 280nm. The mean retention times of phenylephrine, paracetamol, caffeine and chlorpheniramine were found to be 1.8, 3.1, 5.2 and 10.9min, respectively. The method was validated in terms of linearity, range, specificity, accuracy, precision and robustness. The proposed method was successfully applied to the estimation of phenylephrine, paracetamol, caffeine and chlorpheniramine in combined tablet dosage form.