Inclusion Complexation: Liquid Chromatography

Liquid chromatography (LC) may be simply described as an analytical technique used to separate the individual components of a solution based on their relative afRnities for a liquid mobile phase and a stationary phase. There are numerous modes of LC (i.e. reversed-phase, normal-phase, ion exchange) that are commonly classiRed according to the mechanism by which separation occurs. One such mechanism involves the formation of inclusion complexes. An inclusion complex can be deRned as an entity, consisting of two or more molecules, in which one molecule, the ‘host’, noncovalently encapsulates or includes a ‘guest’ molecule. In chromatography, differences in the strength of binding between guest molecules or analytes and a speciRc host allow for separation. The purpose of this article is to review recent applications of inclusion complexation in liquid chromatography. Although a variety of small molecule interactions with macromolecules or polymers have been ascribed to inclusion complexation, the focus of this article is on well-deRned host molecules.