Retention Mechanisms of Capacity Factor with Composition of Organic Modifiers in RP-HPLC

초록

The chromatographic retention behavior of five deoxyribonucleosides(dCyd, dUrd, dGuo, dThd and dAdo) was studied with respect to the mobile phase composition under isocratic conditions in reversed-phase HPLC. The volumn fraction, F, of the organic modifier was changed from 0.05 to 0.03 for methanol, and from 0.05 to 0.12 for acetonitrile, respectively. The experimental datd of nitro and steroid compounds were also considered in order to compare five retention models with various classes of sample. The Langmuir-type retention model (k'=A+B/F) with two parameters shows excellent agreement between the experimental capacity factors and calculated values, although the values calculated by the log-scale quadratic model with three parameters (log k'=LF^2+MF+N) are closer. Unlike the other four retention models, the slope B of the Langmuir-type model can characterize the properties of solute and organic modifier simultaneously. For each solute, the intercept A calculated for acetonitrile and for methanol as organic modifiers are closely coincident.