An investigation of obtaining patterns, structure and diffusion properties of biomedical purpose hydrogel membranes

Abstract

The obtaining patterns of hydrogel membrane coatings based on 2-hydroxyethylmethacrylate/polyvinylpyrrolidone copolymers were investigated. Temperature modes of their synthesis were justified and efficient initiating system – a complex of polyvinylpyrrolidone with iron sulfate, which allows low-temperature synthesis was selected. The structural parameters of the grid and membrane permeability for model substances (electrolytes) and medicines (on the example of sodium diclofenac) were studied. The interrelation of structure and composition of hydrogels with their diffusion-transport properties was established. The mechanism of components transfer from encapsulated hydrogel particles through the membrane was described. This mechanism includes the steps of swelling of the hydrogel membrane, molecular diffusion inside the capsule, mass transfer through the membrane to the surrounding solution. The model of mass transfer of the ensemble of spherical particles coated with a polymeric hydrogel shell was proposed. The model makes it possible to predict the duration and rate of release of the target component from encapsulated particles. The process flow diagram of hydrogel membrane coatings forming was developed to create encapsulated forms of sustained drug release.