resumo
Deep eutectic solvents (DESs), a novel generation of solvents, have recently been described as efficient and timesaving fibrillation agents for proteins. In this context, the present work aims at assessing the effect of the hydrogen bond donor (HBD) of cholinium chloride ([Ch]Cl):carboxylic acid based DESs on the dimensions (length and width) of lysozyme nanofibers (LNFs). Mono-, di- and tri-carboxylic acids (acetic, lactic, levulinic, malic and citric acids) were used to prepare different DES formulations, which were successfully used on the fibrillation of lysozyme. The results showed that the carboxylic acid (i.e. the HBD) plays an important role on the fibrillation efficiency and on the length of the ensuing LNFs with aspect-ratios always higher than those obtained by fibrillation with [Ch]Cl. The longest LNFs were obtained using lactic acid as the HBD with an average length of 1004 +/- 334nm and width of 31.8 +/- 6.8nm, and thus an aspect-ratio of ca. 32. The potential of these protein nanofibers as reinforcing additives was evaluated by preparing pullulan (PL)-based nanocomposite films containing 5% LNFs with different aspect-ratios, resulting in highly homogenous and transparent films with improved mechanical performance. (C) 2018 Published by Elsevier B.V.
palavras-chave
EGG-WHITE LYSOZYME; AMYLOID FIBRILS; TRANSPARENT FILMS; IONIC LIQUIDS; PULLULAN; PROTEIN; AMYLOIDOGENESIS; AGGREGATION; COMPOSITES; ACIDS
categoria
Biochemistry & Molecular Biology; Chemistry; Polymer Science
autores
Silva, NHCS; Vilela, C; Pinto, RJB; Martins, MA; Marrucho, IM; Freire, CSR
nossos autores
Carla Vilela
Professor Auxiliar
Carmen Sofia da Rocha Freire Barros
Investigador Coordenador
Isabel Maria Delgado Jana Marrucho Ferreira
Professor Catedrático
Manuel António Martins da Silva
Investigador
Nuno Helder da Cruz Simões Silva
Investigador
Ricardo Pinto
Investigadoragradecimentos
This work was developed within the scope of the project CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), CQE (FCT Ref UID/QUI/00100/2013) and Green-IT (FCT Ref. UID/Multi/04551/2013) financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. The Portuguese Foundation for Science and Technology (FCT) is also acknowledged for the doctoral grant to N.H.C.S. Silva (SFRH/BD/85690/2012), post-doctoral grants to C. Vilela (SFRH/BPD/84168/2012) and R.J.B. Pinto (SFRH/BPD/89982/2012), and contract under Investigador FCT to C.S.R. Freire (IF/01407/2012).