Analytical review of mechanisms of controlled release of bioactive compounds from poly(2-hydroxyethylmethacrylate)/nanosilica composites

Abstract

The development of new functional composites for directed transport and controlled release of bioactive compounds (BACs) is one of the priority tasks of modern surface chemistry and pharmaceutical technology. The work analyzes hybrid organic/inorganic systems based on poly(2-hydroxyethyl methacrylate) (PHEMA) filled with nanosilica as stimulus-sensitive matrices for biomedical applications. It was established that the kinetics of BACs release from these composites is determined by a combination of their composition and structural parameters. The regulation of the desorption process of components is achieved by creating additional cross-links in the polymer matrix, introducing nanosilica as a filler and using water as a pore former. At the same time, the efficiency of BACs retention by the matrix and the rate of their diffusion significantly depend on the physicochemical parameters of the environment, in particular on the pH value, which is a key factor in modulating interactions in areas with different intensities of the inflammatory process. The presented analytical study summarizes the mechanisms of interaction of BACs with composites based on PHEMA and nanosilica. The limits of dominance of various types of influences, including electrostatic attraction, steric hindrance and the formation of hydrogen bonds during the binding and desorption of BACs, were determined. A comprehensive understanding of these fundamental processes allows us to transform approaches to creating innovative systems with controlled release of BACs in accordance with modern requirements of the pharmaceutical industry.