Potential limitations of recrystallization for the definitive identification of radioactive steroids |
| |
Authors: | Barry D Albertson Rick J Schiebinger Gordon B Cutler SEdward Davis DLynn Loriaux |
| |
Institution: | Developmental Endocrinology Section, Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20205 USA |
| |
Abstract: | The usefulness of recrystallization in establishing the radiochemical purity of steroids is widely recognized, but the potential limitations of the technique have received little attention. The current study reports the failure of standard recrystallization procedures using methanol/water as the solvent pair to separate contaminating 14C-17-hydroxyprogesterone (17-hydroxy-4-pregnene-3, 20-dione) from 3H- and 14C-labeled 11-deoxycortisol (17,21-dihydroxy-4-pregnene-3,20-dione) despite ten serial crystallizations. The standard criteria of radiochemical purity were met despite gross impurity of the crystals as evidenced by thin layer chromatography. Thus, recrystallization may, under certain conditions, yield misleading results when employed as the only method for identifying radioactive steroids. These observations illustrate the importance of an optimal choice of solvent and crystallization conditions, and emphasize the need for confirmation by derivative formation and chromatography. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|