Retention-structure relationship studies for some steroidal hormones in micellar liquid chromatography

The retention behavior in a C-18 column of fourteen steroidal hormones (clo stebol acetate, dehydrotestosterone, dydrogesterone, medroxyprogesterone, m edroxyprogesterone acetate, methandienone, methyltestosterone, nandrolone, nandrolone decanoate, progesterone, testosterone, testosterone enanthate, t estosterone propionate and, stanozolol) with pure micellar mobile phases pr epared from sodium dodecyl sulfate (SDS), and hybrid mobile phases comprisi ng SDS-acetonitrile and SDS-pentanol, was correlated with their octanol-wat er partition coefficients. Similar correlations were found with retention d ata obtained by other authors in gas chromatography, conventional reversed- phase liquid chromatography, and micellar electrokinetic chromatography. Th e retention of the steroids depended on the nature of the R-17 substituent in the steroid tetracyclic system. Steroids of low, intermediate, and high retention had hydroxyl, acetyl, and ester groups, respectively. The retenti on of nandrolone was, however, abnormally high in the presence of micelles, because of the absence of a methyl group at R-10. Retention of the compoun ds in the micellar mobile phases was also evaluated in terms of their solut e-micelle and solute-stationary phase association constants.