THE LIQUID-CHROMATOGRAPHIC SEPARATION OF METABOLITES OF BENZO[A]PYRENE WITH GAMMA-CYCLODEXTRIN AS A MOBILE-PHASE ADDITIVE

The effects of gamma-cyclodextrin as a mobile phase additive on the re tention characteristics of fourteen metabolites of benzo[a]pyrene were investigated with reversed-phase liquid chromatography. It was possib le to separate dihydrodiols, diones, and monohydroxyl-benzo[a]pyrenes as individual classes of metabolites. Also, with gamma-cyclodextrin in the mobile phase, monohydroxyl-benzo [a]pyrene isomers that were very difficult to separate were readily separated. For example, 6-hydroxyl -benzo- [a]pyrene was separated from 12-hydroxyl-benzo[a]pyrene and 9- hydroxyl-benzo[a]pyrene was separated from 2-hydroxyl-benzo- [a]pyrene . The four tetrols were readily separated with shorter retention times using 4.0 mM of gamma-cyclodextrin in a methanol-water (55:45) mobile phase. Overall, the results showed that gamma-cyclodextrin was more e ffective in separating the metabolites than was beta-cyclodextrin.