DESENVOLVIMENTO, CARACTERIZAÇÃO E AVALIAÇÃO DA ATIVIDADE ANTIOXIDANTE DE NANOPARTÍCULAS DE POLI(ÁCIDO-LÁTICO) CONTENDO VANILINA

Abstract

The loading of antitumor agents through polymer nanoparticles is a promising strategy for cancer treatment. Among the compounds that have been highlighted, vanillin is a molecule that has been studied mainly for its antioxidant capacity and also the antimutagenic and chemopreventive character that has demonstrated. However, problems of low solubility and bioavailability inherent characteristics of the molecule itself cause an alternative drug loading it is necessary to overcome this limitation and reach the site of action in effective concentrations. Therefore, this study aimed to the development of PLA polymeric nanoparticles containing vanillin, the physicochemical characterization of these as well as the evaluation of their antioxidant potential in vitro. The nanoparticles were prepared by emulsion solvent evaporation method and characterized as to size, polydispersity index, zeta potential, in vitro release profile, encapsulation efficiency, DSC, IR spectroscopy and x-ray diffraction. An analytical HPLC method was developed and validated for the quantification of vanillin. The average efficiency of vanillin encapsulation in PLA nanoparticles was approximately 41% and the method used was capable of producing particles with nanometric size of 239, with high homogeneity in size distribution, zeta potencial of -22 mV and structure amorphous character. In vitro release assay vanillin nanoparticles showed a initial "burst" effect followed by a sustained and slow release, with the end 120 hours only 22% of the drug was released. In the study of the physical stability of the developed nanoparticles were stable in size, polydispersity index, zeta potential and drug contents during the study period (3 months). Evaluation of antioxidant activity in vitro demonstrated a concentration-dependent and time-dependent inhibition profile of vanillin nanoparticles, since the percentage of inhibition greater concentration was equivalent to that of free drug after 96 hours of incubation. Thus, the set of results shows that the nanostructured system produced PLA for loading vanillin possesses suitable physicochemical characteristics and is able to maintain the antioxidant activity in vitro in the course of drug release.