Produção de membranas de acetato de celulose simétricas e assimétricas para aplicação na liberação dos fármacos ibuprofeno e naproxeno

Abstract

In this work, the cellulose diacetate polymer, known commercially as cellulose acetate (AC), was used as polymer matrix in the processing of symmetric and asymmetric membranes by the Solvent Evaporation Method, using acetone as solvent and water as non-solvent (NS). The reference membranes were produced by adding the proportions 0, 10, 15 and 25% (w/w) NS, without addition of the drugs. Then, membranes were produced in the same mass proportions of NS, with addition of 10% (w/w) of the drugs Ibuprofen (IBF) and Naproxen (NPX), separately, also by Solvent Evaporation Method. Scanning Electron Microscopy (SEM) allowed the evaluation of the addition of different proportions of NS, as well as of each drug on the membrane morphologies. The results of the Thermogravimetric Analysis (TGA) and Differential Exploratory Calorimetry (DSC) allowed a joint analysis of the results in order to verify the existence of interactions of the polymer-drug type (P-D) and to study how these interactions was altered by the morphological modifications induced by the different proportions of NS added and the different drugs studied. Also, drug release assays were carried out in 0.1 mol L-1 phosphate buffer at pH 7.4 at a fixed temperature of 36 ° C and quantified by square wave voltammetry (SWV). Finally, it was possible to identify the existence of the P-D interactions and to determine that they are less intense as the proportions of NS increase. It was also identified that, although NPX shows results indicating more intense P-F interactions than for IBF, the latter showed release results with longer times. From this information and the results and hypotheses formulated during this work, it was concluded that, although the P-D interaction established between AC and NPX drug is apparently more intense, the properties of IBF influenced the solvent evaporation, reducing the volatilization rate of acetone and forming membranes with morphology of size and distribution of pores more uniforms, which guaranteed its greater time of release from the polymer matrices.