Statistical evaluation of the validity of a method for characterizing stationary phases for reversed-phase liquid chromatography based on retention of homologous series

The validity of a method for characterizing stationary phases for reversed-phase liq. chromatog., based on the use of homologous series, was evaluated. The method is based on a retention model which describes the dependence of the logarithm of the capacity factor on mobile phase compn. and the C no. of specific homologous series. A 1st-order as well as a 2nd-order version of this model was studied. The 2nd-order model proved to be a significant improvement on the 1st-order model, even for smaller mobile-phase ranges. Nevertheless both models showed a significant lack of fit, reflecting the incompleteness of these models. Therefore, it is very questionable whether this method is suitable to describe HPLC-column characteristics like hydrophobicity and hydrophlicit