Dynamics of the sorption of phosphatidylcholine by mesoporous composites based on MCM-41

The possibility of predicting the breakthrough curves of a phospholipid (PL) during its sorption by mesoporous composites based on MCM-41 using models of the dynamics of sorption that consider the kinetics of adsorption (the Thomas model) and mixed diffusion (the asymptotic model) is demonstrated using phosphatidylcholine (PC) as an example. The effect the kinetic parameters have on the tailing of the sorption front with respect to the mixed diffusion limitation of the sorption of nonpolar biologically active substances (BASes) is shown. It is found that the ordered structure of composite materials based on MCM-41 ensures a high rate of mass transfer and thus little tailing of the sorption front, when compared to sorbents with a lower degree of order (silica gel and polymer materials) during the sorption of a phospholipid under dynamic conditions. Based on calculations of the parameter of pattern Λ under the conditions of the dynamic mode of sorption in mixed diffusion kinetics, it is shown that the sorption of phosphatidylcholine from hexane solutions by mesoporous composites based on MCM-41 allows the sorption chromatographic process to proceed in the most advantageous (quasi-equilibrium) mode.