resumo
New materials obtained through the incorporation of meso-tetraarylporphyrins, bearing phenyl or pentafluorophenyl groups at the meso positions with or without acid groups, in chitosan films have been prepared and characterized in detail. The efficiency of these porphyrinic-chitosan films (PS-CF) to prevent Listeria innocua attachment and subsequent biofilm formation was evaluated under different irradiation protocols (dark, light, light + dark, dark + light). All tested porphyrinic-chitosan films were photostable and effective in reducing Listeria innocua attachment during a period of 24 h exposure to white light. Biofilm development was nearly completely inhibited in two of the PS-CF films (one containing the 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin and the other one of the thio-carboxylate porphyrins) after being exposed to white light for 24 h followed by incubation in the dark for 48 h. Experiments with the non-immobilized porphyrins against cell suspensions of the same Listeria innocua strain showed that, the photodynamic inactivation efficiency was dependent on porphyrin. The demonstrated antimicrobial activity of PS-CF films, associated with the easy recovery of these films, make them promising photodynamic antifouling materials. (C) 2016 Elsevier Ltd. All rights reserved.
palavras-chave
IN-VITRO; ANTIBACTERIAL ACTIVITY; PACKAGING MATERIAL; INACTIVATION; PORPHYRINS; THERAPY; PHOTOINACTIVATION; PHOTOSENSITIZERS; DERIVATIVES; FILMS
categoria
Chemistry; Engineering; Materials Science
autores
Castro, KADF; Moura, NMM; Fernandes, A; Faustino, MAF; Simoes, MMQ; Cavaleiro, JAS; Nakagaki, S; Almeida, A; Cunha, A; Silvestre, AJD; Freire, CSR; Pinto, RJB; Neves, MDPMS
nossos autores
Armando Jorge Domingues Silvestre
Professor Catedrático
Carmen Sofia da Rocha Freire Barros
Investigador Coordenador
Ricardo Pinto
Investigadoragradecimentos
The authors are grateful to Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior and Universidade de Aveiro for financial support, and CBQF/Escola Superior de Biotecnologia da Universidade Catolica Portuguesa by strains of Listeria innocua. Thanks are also due to FCT/MEC for the financial support to the Organic Chemistry Research Unit (QOPNA) (PEst-C/QUI/UI0062/2013; FCOMP-01-0124-FEDER-037296), CESAM (UID/AMB/50017/2013) and CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), through national founds and when applicable co-financed by the FEDER, within the PT2020 Partnership Agreement and Compete 2020, and also to the Portuguese NMR Network. The Portuguese Foundation for Science and Technology (FCT) is also acknowledged for a research contract under "Investigador FCT 2012" (IF/01407/2012) to C.S.R. Freire. K.A.D.F. Castro also thanks CNPq for her post-doctoral scholarship (Process: 201107/2014-7). N.M.M. Moura further wishes to thank FCT for the post-doctoral scholarship No SFRH/BPD/84216/2012.