Kinetically selective preparative chromatography of biologically active substances on polymeric sorbents

A technique of preparative adsorption chromatography, according to which the separation of substances is determined by the effect of kinetic selectivity of sorption (KSS), is discussed. Unlike traditional chromatography methods, in which separation is determined by the difference in the binding strength of the separated components (distribution coefficients), in kinetically selective chromatography, the separation parameters can be controlled by changing the ratios between the distribution coefficients and the sorption rate of components (effective diffusion coefficients). The necessary and sufficient prerequisites for the inversion of the selectivity of sorption of the components of sorption systems are identified, when the order of components coming off the column is reversed and a component with a higher equilibrium distribution coefficient comes out of the column first. The KSS effect consists in the fact that a component with a higher distribution coefficient is more selectively adsorbed before the selectivity inversion point and a component with a lower distribution coefficient is preferably absorbed after the inversion point. The prospects of practical use of kinetically selective chromatography are considered using systems important for biotechnology and pharmaceutics. The use of the KSS effect allowed us to optimize the separation of a number of biologically active substances both in the case of the inversion of sorption selectivity of the separated components and in those cases when the conditions of the inversion of sorption selectivity were not met.