Impact of chemical structure and substituents of polysaccharide-based chiral stationary phases on cannabinoids retention under normal phase conditions

Polysaccharide derivatives are the most widely used chiral stationary phases (CSP) for the separation of chiral compounds. The availability of multiple adsorption and interaction sites of these CSPs is at the basis of their applicability; indeed, they are considered a quasi-universal SP, but concomitantly, this makes the full understanding of the separation process difficult. In this context, this study is intended to enhance our understanding of the influence of the backbone and substituent type of nine commercial polysaccharide-based CSPs on retention and selectivity of a set of 12 cannabinoids (including cannabichromene, cannabichromenic acid, cannabicyclol, and tetrahydrocannabinol enantiomers) under normal phase conditions. The application of statistical analysis to the results has highlighted a clear distinction between columns bearing electron-withdrawing and electron-donating groups, independent of the backbone. The obtained information are pivotal to fully exploit the potential of these differently substituted CSPs, as well as for the future design of novel chiral selectors.