Filmes de acetato de celulose contendo derivado N-acilidrazônico para tratamento de lesões cutâneas

Abstract

Different raw materials of plant origin have been evaluated as alternative sources of cellulose. However, few studies explore the potential of typical regional crops such as semiarid forages. The objective of this study was to use forage palm (Nopalea cochenillifera (L.) Salm Dyck) as a raw material for cellulose extraction, using it for production and characterization of one of its derivatives, cellulose acetate (ACT). Features such as biodegradability, low toxicity and biocompatibility make this polymer exploited in the pharmaceutical field. Thus, this work also sought to make possible the use of this polymer for the development of polymeric films containing an N-acylhydrazonic derivative called JR19, with promising anti-inflammatory activity for skin lesions and the ACT Sigma Aldrich® for a comparative study. The extraction method is based on the oxidation of lignins that expose the samples to different reaction media. After isolation, the cellulose was submitted to acetylation reaction to replace hydroxyl groups of cellulose, by acetyl groups characteristic of ACT. The obtained ACT was characterized and identified by the degree of substitution, Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD) and optical microscopy. The polymeric films were developed with and without the incorporation of JR19, for this, we used the solvent evaporation method that attested to the speed and effectiveness in membrane formation. Thermoanalytical, spectroscopic characterization techniques, evaluation of mechanical properties and morphological aspects were performed. The obtained results characterized the ACT as predominantly tri substituted derivative, corroborating with the FTIR that indicated the presence of the acetyl groups in the polymer, the XRD showed a characteristic amorphization of the cellulose acetylation process. To date, research has been unsuccessful in the formation of ACT films acquired from the forage palm extractive process, so the development and physical-chemical characterization of Sigma Aldrich® ACT films has been carried out. For the films 1.5% of the polymer, 10% glycerol (plasticizer) and acetone PA with solvent of the polymeric solution were used. A specific, linear, precise, accurate and robust method for quantifying JR19 was developed. Mechanical tests have demonstrated suitability for biomedical application. Microscopies evaluated the change in morphological aspects with and without the addition of JR19, making it possible to visualize porosities in the membranes and the incorporated drug crystals. Thermogravimetric (TG) and Differential Exploratory Calorimetry (DSC) results allowed a combined analysis of the isolated components and films with and without the drug, indicating that there were no polymer / drug interactions. The FTIR expressed the main functional groups of the evaluated samples, indicating that JR19 was incorporated. XRD indicated the suppression of drug crystallinity in the films, which characterizes the incorporation or amorphization of JR19. Thus, forage palm can be used as a raw material in the synthesis of cellulose acetate, and substantially in obtaining innovative formulations, having the adjacent advantage of low cost and valorization of local vegetation. The techniques used allowed characterizing the formulation of ACT and JR19, showing promise for the development of these films / dressings as a new pharmaceutical treatment proposal. The research also aims to evaluate the release profile and toxicological assay of them.