PHYSICAL AND CHEMICAL STABILITY STUDIES ON CEFOTAXIME AND ITS DOSAGE FORMS BY STABILITY INDICATING HPTLC METHOD

The influence of temperature and relative humidity on the stability of cefotaxime sodium in the solid state, continuous infusion and in different doses was investigated. Changes in the concentration of cefotaxime sodium were followed by a HPTLC method. The physical stability parameters of colour change and pH were calculated. The physical and chemical stability of cefotaxime sodium was determined at three different temperatures (5°C, 25°C, and 45°C) and quantified by using a stability indicating HPTLC method. The stability of a drug may also be concentration dependent and hence the stability of cefotaxime IV available in three different doses (1gm, 500mg, and 250 mg) was determined when stored at 45°C. The drug solutions were clear and pale yellow initially with the intensity increasing by time, eventually becoming reddish yellow. HPTLC analysis indicated that 100mg/ml concentration of cefotaxime sodium maintained adequate stability for 2 hours at 45°C and up to 24 hours at 25°C and up to 5 days at 5°C. Decrease in drug concentration by more than 10% from initial concentration was considered unstable (chemical instability). Change in pH by more than 1 was considered unstable. The drug exhibited physical and chemical stability consistent with previously reported stability studies.