ELENA GROSU, ANCUTA TRIFOI, MARIA RAPA, TIMEA GHERMAN, ANDREEA TURCANU, PETRU FILIP STUDY OF THE DRUG DIFFUSION THROUGH POLYMERIC MEMBRANES We present the studies carried out on the transport properties of some membranes obtained from synthetic polymers: polyurethane and ethylene-vinyl acetate copolymer, for use in the development of transdermal therapeutic systems with limiting membranes of speed. The properties of drug active substances transport through membranes were highlighted by performing studies with a diffusion cell. Experimental drug active substances were paracetamol and tetracycline. The experimental data obtained was processed using a general mathematical model for drug release from non-porous, non-swellable transdermal devices, which starts from Fick’s second law and has terms that also take into account the possibility of retaining the drug in the membrane polymer. Even though the mathematical model does not take into account neither the swelling phenomenon nor the possibility of membrane erosion, a good agreement between model and experimental data was obtained. The values of effective diffusion coefficients of drug in the polymeric membranes were also determined.
Keywords: therapeutic transdermal delivery, Fick’s diffusion law, drugs transport through polymeric membranes, modelling