resumo
Novel antibacterial and biocompatible transparent films based on chitosan or pullulan and two bioactive ionic liquids (ILs), cholinium hexanoate and cholinium citrate, were prepared. These ILs were selected based on their MIC values against several microbial strains, film-forming ability when blended with the polysaccharides and biocompatibility against designated human cell lines. The films were obtained through simple casting of polysaccharide aqueous solutions containing different amounts of the ILs (20 and 40 wt% with respect to the amount of polysaccharide). The physical properties of the films were investigated using transmittance measurements, thermal analysis, mechanical testing and antibacterial assays. In general, the addition of both ILs does not affect the optical transparency (up to 80% transmittance within 400-700 nm) of the films but decreased their stiffness (acting as plasticizers) and thermal stability. All chitosan-based films showed antibacterial activity against S. aureus and K. pneumoniae but for pullulan only those with cholinium citrate were bioactive.
palavras-chave
NATURAL-BASED POLYMERS; BARRIER PROPERTIES; 1-ETHYL-3-METHYLIMIDAZOLIUM ACETATE; NANOFIBRILLATED CELLULOSE; BACTERIAL CELLULOSE; COMPOSITE FILMS; CHITOSAN; STARCH; DISSOLUTION; PULLULAN
categoria
Chemistry; Science & Technology - Other Topics
autores
Tome, LC; Silva, NHCS; Soares, HR; Coroadinha, AS; Sadocco, P; Marrucho, IM; Freire, CSR
nossos autores
Carmen Sofia da Rocha Freire Barros
Investigador Coordenador
Liliana C. Tomé
Estudante de doutoramento
Nuno Helder da Cruz Simões Silva
Investigadoragradecimentos
Liliana C. Tome, Nuno H.C.S. Silva and Hugo R. Soares are grateful to FCT (Fundacao para a Ciencia e a Tecnologia) for the PhD research grants SFRH/BD/72830/2010, SFRH/BD/85690/2012 and SFRH/BD/81598/2011, respectively. Isabel M. Marrucho and Carmen S.R. Freire acknowledge FCT/MCTES (Portugal) for contracts under Investigador FCT 2012. This work was supported by FCT through the projects, Pest-OE/EQB/LA0004/2013 (ITQB) Research Unit GREEN-it