abstract
Cashew gum (CG), an exudate polysaccharide from Anacardium occidentale trees, was carboxymethylated (CGCm) and oxidized (CGO). These derivatives were characterized by FTIR and zeta potential measurements confirming the success of carboxymethylation and oxidation reactions. Nanostructured multilayered films were then produced through layer-by-layer (LbL) assembly in conjugation with chitosan via electrostatic interactions or Schiff bases covalent bonds. The films were analyzed by QCM-D and AFM. CG functionalization increased the film thickness, with the highest thickness being achieved for the lowest oxidation degree. The roughest surface was obtained for the CGO with the highest oxidation degree due to the predominance of covalent Schiff bases. This work shows that nanostructured films can be assembled and stabilized by covalent bonds in alternative to the conventional electrostatic ones. Moreover, the functionalization of CG can increase its feasibility in multilayers films, widening its potential in biomedical, food industry, or environmental applications. (C) 2017 Elsevier Ltd. All rights reserved.
keywords
ANACARDIUM-OCCIDENTALE GUM; ATOMIC-FORCE MICROSCOPY; TREE GUM; DRUG-DELIVERY; MULTILAYER FILMS; EXUDATE POLYSACCHARIDE; ANTIMICROBIAL ACTIVITY; RHEOLOGICAL PROPERTIES; CONJUGATED POLYMERS; EXPONENTIAL-GROWTH
subject category
Chemistry; Polymer Science
authors
Leite, AJ; Costa, RR; Costa, AMS; Maciel, JS; Costa, JFG; de Paula, RCM; Mano, JF
our authors
Ana Margarida Silva Costa
PhD Student
João Mano
Vice DirectorGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
This work was supported by the Portuguese "Fundacao para a Ciencia e Tecnologia" (FCT) [SFRH/BD/73174/2010, SFRH/BPD/95446/2013]; "Fundo Social Europeu" (FSE),"Programa Operacional de Capital Humano" (POCH), and the Brazilian "Conselho Nacional de Desenvolvimento Cientifico e Tecnologico" (CNPq) [202101-2014].