Efeito da luz branca sobre a atividade fungicida de partículas de cobre em filme compósito PMMA-PVA

Abstract

Copper is a metal with wide application in history, being widely used today as a way to conduct electricity, however, its properties go beyond this, being also used as a sanitary material with antimicrobial and antiviral properties. This property in particular was researched and analyzed for applications of antimicrobial and antiviral materials in various ways, including the application of composite films with metal microparticles, which the present work intends to apply and explore with a fungal pathogen, Candida albicans. These copper microparticles have photoreactive properties, which, based on the literature, can be amplified by the action of light. Composite films are generally formed by a polymeric matrix and an additive, which has a property to be applied, in this context, composite films with copper have properties intrinsic to this metal, in addition, the choice of a polymeric matrix concerns what type of behavior is expected from the film, therefore, the choice of polymers with biodegradability and mechanical resistance were a fundamental part of defining the polymeric matrix that best suited the purpose of this work. As a polymeric matrix, PVA and PMMA were chosen, with 2.5% w/v for both in Dimethylformamide, diluted at 100°C for 4 hours under constant agitation, based on the literature, a concentration of 2% w/v was used. v of copper dispersed through ultrasonification in the polymeric solution, in this way, two films were produced, corresponding to the white one, without copper, and the composite, with copper. To characterize the composite film, techniques such as SEM-EDS, XRD, UV-Vis, FTIR and GDOES were used, and to evaluate the antifungal activity against Candida albicans under the effect of white light and the absence of light, a procedure adapted from the standard was used. JIS Z 2801. Through these tests, it was verified that the film has an average thickness of 65.3 ?m, with signs of copper reported along the outermost layer of the film, however, at higher internal concentrations, it was also verified that the PVA and PMMA are present, making it possible to characterize them through absorption peaks in FTIR analyses. For the antifungal tests carried out under different lighting conditions, it was noticeable that the film had an antifungal action and that this property was amplified by the presence of light, being considered a promising result for future applications. [resumo fornecido pelo autor]