resumo
The design of cheap and safe antibacterial materials for widespread use has been a challenge in materials science. The use of copper nanostructures combined with abundant biopolymers such as cellulose offers a potential approach to achieve such materials though this has been less investigated as compared to other composites. Here, nanocomposites comprising copper nanofillers in cellulose matrices have been prepared by in situ and ex situ methods. Two cellulose matrices (vegetable and bacterial) were investigated together with morphological distinct copper particulates (nanoparticles and nanowires). A study on the antibacterial activity of these nanocomposites was carried out for Staphylococcus aureus and Klebsiella pneumoniae, as pathogen microorganisms. The results showed that the chemical nature and morphology of the nanofillers have great effect on the antibacterial activity, with an increase in the antibacterial activity with increasing copper content in the composites. The cellulosic matrices also show an effect on the antibacterial efficiency of the nanocomposites, with vegetal cellulose fibers acting as the most effective substrate. Regarding the results obtained, we anticipate the development of new approaches to prepare cellulose/copper based nanocomposites thereby producing a wide range of interesting antibacterial materials with potential use in diverse applications such as packaging or paper coatings.
palavras-chave
SILVER NANOPARTICLES; ESCHERICHIA-COLI; ANTIMICROBIAL ACTIVITY; CYTOTOXICITY; GENOTOXICITY; CHITOSAN; SIZE
categoria
Biotechnology & Applied Microbiology; Research & Experimental Medicine
autores
Pinto, RJB; Daina, S; Sadocco, P; Neto, CP; Trindade, T
nossos autores
agradecimentos
Ricardo Pinto thanks the Portuguese Foundation for Science and Technology (FCT) for Grant no. SFRH/BPD/89982/2012. The authors also acknowledge FCT (PEst-C/CTM/LA0011/2011), Fundo Social Europeu (FSE), and Programa Operacional Potencial Humano (POPH) for funding. Microscopy analysis was supported by Rede Nacional de Microscopia Eletronica (RNME-Pole UA FCT) Project REDE/1509/RME/2005.