Development and Validation of RP-HPLC Method for the Analysis of Cobicistat and Related Impurities in Bulk and Pharmaceutical Dosage forms

The prime aim of the current work is to develop and validate a novel, specific, sensitive, precise, rapid and faster isocratic elution, RP HPLC method for estimation of Cobicistat and related impurities in bulk and pharmaceutical dosage forms. Chromatographic separation was achieved on Inertsil ODS - 3V column (250 mm X 4.6 mm, 5μ) using an isoratic mode with mobile phase composed of potassium dihydrogen phosphate buffer (PH 2.5) and acetonitrile in the ratio of 30:70 v/v. The flow rate was 1.0ml/min, temperature is maintained at ambient and detection was made at 240 nm. The run time was 15 min. The developed method was validated according to the ICH guide lines and different analytical parameters such as linearity, precision, accuracy, specificity, limit of detection, limit of quantitation were determined. The linearity of calibration curve for each analyte in concentration range of 400 μg/ml -1200μg/ml. is good. There exists good correlation between peak area and analyte concentration. Relative standard deviation values for cobicistat is 0.099 and impurity is 0.6636. LOD for drug and impurity is 0.02 % and 0.20 % respectively. LOQ for drug and impurity is 0.06 % and 0.60% respectively. Hence the proposed method is highly sensitive, precise, accurate, robust and fast. The short retention time allows the analysis of large number of samples in short period of time and it is cost effective, so it can be successfully applied for routine analysis of active pharmaceutical ingredient and related impurities in bulk and pharmaceutical dosage forms.