Original Articles
P. Suguna, B. Sathyanarayana,
Abstract
A simple, economic, selective, precise, and accurate high performance liquid chromatographic method for the analysis of methotrexate in bulk drug and pharmaceutical formulations was developed and validated in the present study. The mobile phase consists of a mixture of acetonitrile and potassium dihydrogen orthophosphate in the proportion 92:8, a kept at the pH to 6.0 ± 0.05 with sodium hydroxide solution. This was found to give a sharp peak of methotrexate at a retention time of 4.517min. HPLC analysis of methotrexate was carried out at a wavelength of 303 nm with a flow rate of 1.4ml/min. The linear regression analysis data for the calibration curve showed a good linear relationship with a regression coefficient of 0.999 in the concentration range of 50 μg ml-1 to 150 μg ml-1. The linear regression equation was y =37.771X - 413.07. The developed method was employed with a high degree of precision and accuracy for the analysis of ethotrexate. The developed method was validated for accuracy, precision, robustness, detection and quantification limits in accordance with as per the ICH guidelines. The wide linearity range, accuracy, sensitivity, short retention time and composition of the mobile phase indicated that this method is better for the quantification of methotrexate.