High-performance liquid chromatographic separation and identification of epimeric 17-ketone impurities in commercial sample of dexamethasone sodium phosphate
✍ Scribed by Eric C. Juenge; James F. Brower
- Publisher
- John Wiley and Sons
- Year
- 1979
- Tongue
- English
- Weight
- 524 KB
- Volume
- 68
- Category
- Article
- ISSN
- 0022-3549
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✦ Synopsis
A commercial sample of dexamethasone sodium phosphate solution for injection was found to contain 56% of the label concentration and to be extensively contaminated (approximately 50%) with a white insoluble solid, which was identified as a mixture of the 16 alpha- and 16 beta-methyl epimers of 9-fluoro-11 beta-hydroxy-16-methylandrosta-1,4-diene-3,17-dione. High-performance liquid chromatography (HPLC) was used to separate, identify, and quantitate these epimers and to determine their presence in commercial samples. One epimer was identified by HPLC comparison with a synthesized specimen of 9-fluoro-11 beta-hydroxy-16 alpha-methylan-drosta-1,4-diene-3,17-dione. The second peak was identified as the 16 beta-epimer by epimerization of the synthesized alpha-component with alkali to obtain a product whose chromatogram matched that of the impurity. These conclusions are supported by data obtained by IR and UV spectrophotometry, TLC, and the blue tetrazolium test.