Methods for modeling in vitro percutaneous absorption of drugs from local dosage forms

Transdermal absorption of medicinal substances (LP) proceeds as a two-stage process, consisting of penetration of drugs from dosage forms (LF) into the skin and absorption itself [4]. In biopharmaceutical studies, when choosing the optimal composition of dermal DF and studying the role of pharmaceutical factors affecting the release of drugs from LF, dialysis methods (equilibrium and flow) are widely used, designed to simulate both stages of transdermal absorption. A number of requirements are imposed on model membranes, which are a diffusion barrier: they must have an insignificant thickness and a small internal volume so that the amount of LS remaining in it is minimal; be sufficiently resistant to mechanical stress so that during the experiment its integrity is not violated; should provide a correlation between the results of experiments in vivo and in vitro [5, 6, 10].