Síntesis solvotermal de nanopartículas de cobre, su encapsulación en la matriz quitosano/capsaicina y estudio de liberación

Abstract

In the present work, the synthesis of copper nanoparticles (Cu-NPs) by a solvothermal method, and its incorporation in chitosan/capsaicin spheres and with its subsequent release studies, is reported. The Cu-NPs were synthesized by two routes, the first using ethylene glycol as solvent and the second using oleylamine at different conditions of temperature and time of synthesis. The obtained Cu-NPs were characterized by MET, UV-Vis, and IRTF and presented an average size of 9 nm and cubic morphology. In the second instance, capsaicin was extracted from chili pepper (Capsicum Pubescens) using the Soxhlet method. The extract of capsaicin obtained was a percentage of extraction of 30.64% and a concentration of capsaicin of 2134 ppm from the seeds of chili. As a third phase, Cu-NPs and capsaicin were incorporated into spheres and fibers by ionic gelation and electrospinning, respectively. Spheres and fibers were characterized by MEB and IRTF, and spheres with a size of 1.25 mm, with a porous structure and with Cu-NPs incorporated were obtained, also fibrous structures with particle agglomerates (Cu-NPs) interconnected by fibers were obtained by electrospinning. Finally, tests were carried out on the release of capsaicin and Cu-NPs from (spheres and fibers) and the release kinetics of each component was evaluated. The released amount of capsaicin and Cu-NPs was quantified by UV-Vis using capsaicin calibration curves and the colorimetric method with the formation of the tetraamino-copper (II) complex [(Cu(NH3)4]2+. The total amount of capsaicin added It was released faster from the fibers than from the spheres, while the Cu-NPs were released in a more controlled manner from the fibers. The kinetic model of release to which the release profiles were best adjusted, both capsaicin and Cu-NPs, was the model of Korsmeyer and Peppas.