Abstract
A validated stability indicating thin layer chromatographic (TLC) method was developed to analyze rosuvastatin calcium (ROS) and its degradation products (DPs). All stress conditions recommended by the international conference on harmonization (ICH) including oxidative, photolytic, thermal, acidic, and basic hydrolysis were applied. ROS and its DPs were selectively separated using aluminum plates precoated with silica gel 60F(254) as a stationary phase and chloroform: n-hexane:methanol:glacial acetic acid (8:10.4:1.5:0.1v/v/v/v) as a developing system. ROS was found to be highly sensitive to photolysis and oxidation and to less extent to acidic hydrolysis. The chemical structures of major DPs were characterized using LC-ESI-MS where two of them were proposed to be the optical isomer and the lactone form of ROS. The peak area of scanned spots and the concentration were correlated using a polynomial regression equation in the range of 0.5-20 mu g/spot with good determination coefficient (R-2=0.9994). The limit of detection and limit of quantitation values were 0.17 and 0.5 mu g/spot, respectively. The intra-day and inter-day precision RSD values were less than 1.49%. The proposed method was successfully applied to the determination of ROS in presence of its DPs in bulk and tablets.