ABSTRACT
In liquid chromatography (LC), various types of bonds are involved in the interactions between mobile phase components and analyte molecule, between stationary phase and analyte molecule, as well as between mobile phase components and the surface of stationary phase. The partition of ionic species between mobile and stationary phase is important in at least two widely used LC separation mechanisms, such as ion chromatography and hydrophilic interaction LC. Intermolecular forces can be attractive or repulsive. Generally, they are separated into two main groups, depending on the distance between interacting species, namely the short-range and long-range forces. The mechanism of retention and separation in ion chromatography consists of ionic equilibria, and it is based on the difference in the affinity for the column of the ionic species that are separated. For the retention, the ions of the analyte should have higher affinity for the column than the counterions preexistent in the resin.
