Revealing the Hydration of Sorbates Based on the Dependence of Their Retention Parameters in Reversed-Phase HPLC on the Concentration of the Organic Component of the Eluent

摘要

parameters of sorbates in reversed-phase high-performance liquid chromatography t(R) depend to the greatest extent on concentration of the organic component C in the eluent. To find weaker pronounced effects against such a "background", approximation of the retention parameters with the use of recurrent first-order correlations t(R)(C + delta C) = at(R)(C) + b is required. For the sorbates that do not form hydrates (K-hydr > 1), the corresponding dependences are linear (the correlation coefficients generally exceed 0.999). If, however, hydration constants of the sorbates K-hydr asymptotic to 1, deviations from linearity are observed. Such abnormalities are the most pronounced in the case of the use of acetonitrile-water eluents, while they are less noticeable in the case of methanol. The reason for this most likely consists in the fact that methanol forms more stable hydrates in comparison with other compounds.