SEPARATION OF POLYCYCLIC AROMATIC HYDROCARBON METABOLITES BY GAMMA-CYCLODEXTRIN-MODIFIED MICELLAR ELECTROKINETIC CHROMATOGRAPHY WITH LASER-INDUCED FLUORESCENCE DETECTION

Using a modified micellar buffer consisting of gamma-cyclodextrin (gam ma-CD) and sodium dodecyl sulfate (SDS), we have obtained separations of hydroxy-polycyclic aromatic hydrocarbons (hydroxyPAHs). These compo unds are oxidative products of mammalian PAH metabolism. The analytes were detected with a commercial laser-induced fluorescence (LIF) detec tor. A number of hydroxyPAH isomers could be separated by changes in g amma-CD concentration. Baseline resolution of 12 hydroxyPAHs was obtai ned using 30 mM berate, 60 mM SDS and 40 mM gamma-CD. The particular s ite substitution of the hydroxy group can produce changes in the hydro xyPAH fluorescence spectrum, and the effect of optical filter selectio n was studied for the LIF detection. The mass detection limits were in the (0.08-0.5)x10(-15) mol range. To our knowledge, this is the first report of the separation of metabolic products of PAHs (and several p ositional isomers) using gamma-CD and micellar electrokinetic chromato graphy. (C) 1998 Elsevier Science B.V.