Theoretical and empirical models in hydrophilic interaction liquid chromatography

Abstract

Hydrophilic interaction liquid chromatography (HILIC) has found application in the determination of polar molecules. This alternative type of chromatography has become increasingly popular in the last five years and a considerable number of articles regarding the elucidation of its retention mechanisms and the development of methods are available. In order to achieve these goals, various types of theoretical and empirical mathematical models were utilized. However, the knowledge obtained from these models was the subject of various interpretations. The goal of this article is to list and discuss the papers in which these models were used in HILIC and give proper theoretical background of the models. In general, theoretical models in HILIC were applied in order to acquire the knowledge of dominant processes in the retention mechanism, retention prediction, and quantitative description of the influence of mobile phase-related factors on the retention and selectivity of the analytes on different types of stationary phases. In addition, empirical models were used for detailed assessment of the retention behavior in terms of both single factor and factor interactions influence on analyte retention and selectivity. Furthermore, they have also shown a great potential in the optimization of HILIC methods in the method development process.