Abstract
A validated RP-HPLC method was developed for the estimation of paracetamol, caffeine, metoclopramide and ergotamine simultaneously in bulk and pharmaceutical formulation. The method was extended for the determination of two paracetamol genotoxic and nephrotoxic impurities and degradation products namely p-aminophenol and 4-chloroacetanilide. Separation was done on octadecyl column (15 cm x 2.1 mm, 5 mu m). Gradient elution was performed using mobile phase consisting of acetonitrile and water (pH 3) in ratio of (20: 80, v/v) for the first 3 min, (50: 50, v/v) for the next 4.5 min, then (20: 80, v/v) for the final 2.5 min. The flow rate was 0.7 mL/min throughout the run which took 10 min. UV detection was done at 230 nm. The proposed method agreed with ICH guidelines of method validation. The suggested method was applied for the estimation of the proposed drugs in their dosage form. Statistical comparison was done between the results obtained from the suggested method and those obtained from reported HPLC method. The proposed method is more beneficial than the published one because of having higher sensitivity and selectivity as it allows the detection of the proposed drugs in lower concentrations in the presence of paracetamol toxic impurities, p-aminophenol and 4-chloroacetanilide.