The aim of the work is to develop and validate the simple, fast and precise stability indicating high performance liquid chromatography method for the separation and quantification of acetaminophen and guaiphenesin in pharmaceutical dosage form. The quantification was carried out using Symmetry C18 (4.6x150 mm, 3.5 µm) enhanced polar selectivity column and mobile phase comprised of potassium dihydrogen phosphate buffer pH 2.5 and methanol in proportion of ratio 65:35v/v. The flow rate was mL/min and the effluent was monitored at 228 nm. The retention time of acetaminophen and guaiphenesin were 2.6 and 4.6 min respectively. Linearity of acetaminophen and guaiphenesin were in the range of
50 to 90 µg/mL and 30 to 55 µg/mL respectively with correlation coefficients 0.999. The percentage recoveries were 99.80% and 99.85% for acetaminophen and guaiphenesin respectively. There was complete separation of degradation peaks and analyte peaks, which demonstrate the specificity of assay method in the presence of its degradation products; it can be employed as a stability indicating one. Due to simplicity, rapidity and accuracy of the proposed Stability Indicating High Performance Liquid Chromatography method, it is used for analysis of stability samples of Acetaminophen and Guaiphenesin in quality control laboratories.
Acetaminophen, Guaiphenesin, RPHPLC method, Validation, Stability studies