In RPLC, the factors
which influence the separation process can be understood by a thorough
analysis of k′ data obtained for a set of compounds using Snyder's solvent
strength plots (see Eq. (1)), where ln kw is the logarithm of the retention
factor for the compound in a purely aqueous medium, B is the
slope of the plot, which is dependent on the solute and the chromatographic
system investigated (mobile and stationary phase), and Φ is
the volume percentage of organicmodifier in themobile phase. Snyder's
solvent strength plots can also be used to predict selectivity and resolution
for a particular separation over a narrow range of Φ