Atividade antimicrobiana de filmes de policloreto de vinila (PVC) reforçado com nanopartículas de prata imobilizadas em sílica
Data
2019-07-05
Autores
Brasil, Edneide Morais
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Objetivo. Analisar a eficácia antimicrobiana in vitro de compósito em pó a base de prata e sua aplicação em diferentes concentrações em filmes de policloreto de vinila (PVC) produzidos em escala industrial e em laboratório. Métodos. Um material compósito constituído por dióxido de sílicio (SiO2) e nanopartículas de prata (NpAg), produzido e cedido por uma empresa de soluções tecnológicas, foi caracterizado por Microscopia Eletrônica de Varredura (MEV), Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) e Difração de Raio X (DRX). Filmes de PVC industrial aditivados com 6,25, 12,5, 25 e 100 ppm de NpAg e filmes produzidos laboratorialmente pelo método de casting aditivados com 12,5, 25 e 100 ppm de NpAg foram caracterizados por Microscopia Eletrônica de Varredura (MEV), Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) e Difração de Raio X (DRX). Testes microbiológicos in vitro foram realizados com o compósito de prata e com os filmes de PVC. Com o compósito realizou-se o Teste de Difusão em Ágar por poço e a Contagem de Microrganismos Viáveis. Com os filmes industrial e laboratorial realizou-se o teste da Norma JIS Z 2801:2000, e com os filmes industriais realizou-se os testes de Agitação em Frasco e Contagem de Microrganismos Viáveis. Resultados. O compósito apresentou inibição para Escherichia coli em todas as concentrações estudadas e para Staphylococcus aureus nas concentrações de 12,5, 25 e 100 ppm de NpAg. A adição de compósito na matriz polimérica do PVC não alterou as propriedades físico-químicas dos filmes. Os filmes industriais apresentaram taxa de inibição baixa para Escherichia coli e Staphylococcus aureus segundo a Norma JIS e os filmes produzidos em laboratório apresentaram inibição alta para Staphylococcus aureus apenas na concentração de 100 ppm de NpAg (97,95%). Em meio líquido, os filmes industriais não apresentaram redução microbiana para ambos microrganismos. Conclusão. Conclui-se que não houve uma boa interação entre a sílica e o polímero, ocasionando aglomerações de compósito no interior dos filmes e consequente diminuição da ação antimicrobiana das nanopartículas. Filmes casting apresentaram uma alta taxa de inibição contra S. aureus na concentração de 100 ppm possivelmente devido à ausência de aditivos no polímero.
Purpose. Analyze the in vitro antimicrobial efficacy of powder silver composites and its applications in different types of polyvinyl chloride (PVC) films in industrial and laboratory scale. Methods. A composite material consisting of silicon dioxide (SiO2) and silver nanoparticles (NpAg), produced and supplied by a company of technological solutions, was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Industrial PVC films added with 6.25, 12.5, 25 and 100 ppm of NpAg and laboratorial films produced by the casting method added with 12.5, 25 and 100 ppm of NpAg were characterized by Scanning Electron Microscopy (SEM), Infrared Spectroscopy with Fourier Transform (FTIR) and X-Ray Diffraction (XRD). In vitro microbiological tests were performed with the silver composite and the PVC films. With the composite, the Agar Diffusion Test per Well was made and the Counting of Viable Microorganisms. The JIS Z 2801: 2000 standard was tested with the industrial and laboratory films, and with the industrial films were carried out Flask Shake and Counting of Viable Microorganisms tests. Results. The compound presented inhibition for Escherichia coli at all concentrations studied and for Staphylococcus aureus at concentrations of 12.5, 25 and 100 ppm of NpAg. The addition of composites in the polymeric matrix of PVC does not altered the physical-chemical properties of the films. Industrial films had a low inhibition rate for Escherichia coli and Staphylococcus aureus according to the JIS Standard and the films produced in the laboratory showed high inhibition for Staphylococcus aureus only at the concentration of 100 ppm of NpAg (97,95%). In the liquid medium, the industrial films does not presented antimicrobial action for both microorganisms. Conclusion. It was concluded that there was no good interaction between silica and polymer, causing agglomerations of compounds within films and consequent loss of antimicrobial action of nanoparticles. The casting films presented a high inhibition rate against S. aureus at a concentration of 100 ppm, possibly due to the absence of additives in the polymer. the concentrations of composites utilized in the PVC films, as well as the distribution of the material in the polymer they were not enough to reduce the concentration of the microorganisms.
Purpose. Analyze the in vitro antimicrobial efficacy of powder silver composites and its applications in different types of polyvinyl chloride (PVC) films in industrial and laboratory scale. Methods. A composite material consisting of silicon dioxide (SiO2) and silver nanoparticles (NpAg), produced and supplied by a company of technological solutions, was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Industrial PVC films added with 6.25, 12.5, 25 and 100 ppm of NpAg and laboratorial films produced by the casting method added with 12.5, 25 and 100 ppm of NpAg were characterized by Scanning Electron Microscopy (SEM), Infrared Spectroscopy with Fourier Transform (FTIR) and X-Ray Diffraction (XRD). In vitro microbiological tests were performed with the silver composite and the PVC films. With the composite, the Agar Diffusion Test per Well was made and the Counting of Viable Microorganisms. The JIS Z 2801: 2000 standard was tested with the industrial and laboratory films, and with the industrial films were carried out Flask Shake and Counting of Viable Microorganisms tests. Results. The compound presented inhibition for Escherichia coli at all concentrations studied and for Staphylococcus aureus at concentrations of 12.5, 25 and 100 ppm of NpAg. The addition of composites in the polymeric matrix of PVC does not altered the physical-chemical properties of the films. Industrial films had a low inhibition rate for Escherichia coli and Staphylococcus aureus according to the JIS Standard and the films produced in the laboratory showed high inhibition for Staphylococcus aureus only at the concentration of 100 ppm of NpAg (97,95%). In the liquid medium, the industrial films does not presented antimicrobial action for both microorganisms. Conclusion. It was concluded that there was no good interaction between silica and polymer, causing agglomerations of compounds within films and consequent loss of antimicrobial action of nanoparticles. The casting films presented a high inhibition rate against S. aureus at a concentration of 100 ppm, possibly due to the absence of additives in the polymer. the concentrations of composites utilized in the PVC films, as well as the distribution of the material in the polymer they were not enough to reduce the concentration of the microorganisms.
Descrição
Palavras-chave
policloreto de vinila, nanopartículas de prata, atividade antimicrobiana, polyvinyl chloride (PVC), silver nanoparticles, antimicrobial activity