Mobile Phase Effects in the Reversed-Phase Liquid Chromatographic Separation of

The isocratic separation of five coenzyme Q homologs (CoQ 6 to C0Q10) by non-aqueous reversed-phase liquid chromatography was investigated. Seven different binary mobile phases were examined in order to determine which produced optimal resolution between the first two homo-logs in a given analysis time. Only small variations (1.42 to 1.45) in a, the group selectivity for the homologous series, were noted for the mobile phases that utilized acetonitrile as weak solvent when the retention of C o Q 1 0 was held constant. Larger variations were noted in plate counts among the various mobile phases and this factor, rather than selectivity, determined the optimal mobile phase. When the capacity factor (k') of C0Q10 was fixed at 5, a methyl t-butyl ethenacetonitrile mobile phase gav