HYDROLYTIC DEGRADATION STUDY OF ROXADUSTAT BY RP-HPLC AND HPTLC

Abstract

Objective: Simple, rapid RP-HPLC and HPTLC methods have been developed in order to study the degradation of Roxadustat under various stress conditions. The Kinetics of hydrolytic degradation is studied. Methods: Optimum separation of Roxadustat and its degradation products was achieved using the following conditions in HPLC, Agilent eclipse XDB-C8 (150×4.6 mm) column, the mobile phase was composed of methanol: phosphate buffer (pH 5, 0.05 M) (70:30 v/v) with UV detection at 262 nm. The flow rate was at 1.0 ml/min. The RT was 4.6±0.02 min. HPTLC work for Roxadustat was performed on Aluminium plates precoated with silica gel 60 F254, (10 cm × 10 cm with 250 μm layer thickness). The mobile phase was composed of Toulene: Ethyl Acetate: Glacial acetic acid (5:5:0.5 v/v/v) and then scanned. The system was found to give a compact spot for Roxadustat (Rf value of 0.58±0.02). Results: In HPLC the calibration curves plotted were found to be linear over the concentration range of 2.5-25μg/ml, with a correlation coefficient of R2=0.9994. In HPTLC the calibration curves plotted were found to be linear over the concentration range of 500-2500 ng/band, with a regression coefficient of R2=0.9957. The analytical performance of the proposed methods was validated as per ICH Q2 (R1) guidelines. The degradant peaks were well resolved from the Roxadustat peak. Significant degradation was observed in acid hydrolysis, alkali hydrolysis, and oxidative degradation. The drug is relatively stable towards photolysis, neutral hydrolysis, and thermal conditions. Conclusion: In the current work, simple RP-HPLC and HPTLC analytical methods for the determination of Roxadustat in the presence of its degradation products have been developed. The information presented herein could be very useful while developing formulation procedures to prevent hydrolytic degradation. It can be used as a routine quality control test.