PREPARATION OF PHENYL TREATED PACKING MATERIALS FOR HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY - EVALUATION BY RETENTION BEHAVIOR OF CARBAMAZEPINE AND DIPHENYLHYDANTOIN

The retention behavior and selectivity of 30 kinds of phenyl-modified porous glasses and silicas, prepared from solutions of phenyldimethylchlorosilane, diphenylmethylchlorosilane or triphenylchlorosilane in xylene, were studied by high-performance liquid chromatography using carbamazepine and diphenylhydantoin as model compounds. From the elemental data for carbon, the maximum number of bonded phenyl groups per gram (mean pore diameter, 15 nm, specific surface area, 21 m2/g, pore volume, 0.85 ml/g) on the diphenyl-bonded glass surface was calculated to be 0.159 x 10(21). Using various acetonitrile-0.01 M potassium dihydrogen phosphate mixtures as eluents, carbamazepine and diphenylhydantoin were separated on all the gels studied, but the degrees of resolution of the two compounds were different. With an increase in specific surface area on the glasses or silicas, the k' values of the solute increased.