HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC SEPARATION OF EQUILIN, ESTRONE, AND ESTRONE DERIVATIVES WITH CYCLODEXTRINS AS MOBILE-PHASE ADDITIVES

beta-Cyclodextrin and two derivatized beta-cyclodextrins were utilized as mobile phase additives for the liquid chromatographic resolution o f equilin and estrone, as well as estrone from 2-hydroxyestrone, 4-hyd roxyestrone, and 16 alpha-hydroxyestrone on a C-18 stationary phase. b eta-Cyciodextrin proved to be suitable for the separations of these st eroids but the modified beta-cyclodextrin provided better resolution. A comparison was made of the separation and retention obtained with be ta-cyclodextrin with that of the modified beta-cyclodextrins, Apparent inclusion complex strengths for estrone and its derivatives with each cyclodextrin were calculated. The effects of mobile phase cyclodextri n concentration and methanol content on selectivity and capacity facto r were examined.