[Dexamethasone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences]

The raw material for dexamethasone sodium phosphate was examined for the preparation of the "Dexamethasone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: pH, 8.0; optical rotation, [alpha]D20 = +79.6 degrees; UV spectrum, lambda max of 242 nm and specific absorbance in water at 242 nm = 313.6; IR spectrum, same as that of the Dexamethasone Sodium Phosphate Reference Standard (Control 893); free phosphoric acid, 0.06%; free dexamethasone, 0.07%; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.2%; residual solvent, 4.3% (ethanol); water, 7.3%. Based on the above results, the raw material was authorized as the Dexamethasone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.