Study of Dissolution Kinetics of Mefenamic Acid Solid Dispersion with Polyvinylpyrrolidone [Исследование кинетики растворения твердой дисперсии мефенамовой кислоты поливинилпирролидоном]

The low solubility of a biologically active substance in an aqueous medium is often the main reason for the reduced therapeutic effect of drugs. The most common approach to solve this problem is to obtain a watersoluble salt of the active substance and an appropriate preparatory formulation based on it. In this case, the solubility of the obtained compound in hydrophobic systems decreases dramatically, which decreases the rate of transmembrane transport and changes the pharmacokinetic laws of the process. In practice, not only the dependence of the therapeutic effect on the salt compound properties, but also a complete loss of the drug active ingredient activity can be observed. The use of biologically active compound solid dispersions in watersoluble polymers is the most promising approach to increase the therapeutic effect of drugs while maintaining the hydrophobic nature of the active component, to reduce the dose load on the patient's body and obtain prolonged action. In experiments we obtained solid dispersions of mefenamic acid in polyvinylpyrrolidone and studied kinetic regularities of solubility of this promising drug form in aqueous solution of phosphate buffer. By means of mathematical modelling it was found that the phenomenon under study is well described by Ritger - Peppas model, which considers diffusion of biologically active component into solution according to Fick's law with possible influence on mass transfer at swelling and degradation of polymer matrix. © 2021 Bauman Press. All rights reserved.