Novel, multifunctional mucilage composite films incorporated with cellulose nanofibers

In the current study, mucilage composite films were produced by incorporating the cellulose nanofibrils (CNF) at different concentrations i.e.,3 and 6% to chia mucilage matrix by solution casting method. To evaluate the effect of CNF incorporation into mucilage matrix, the obtained composite films were characterized extensively using both physicochemical and biological tools. FT-IR spectra confirmed the composite formation by broader –OH bond peaks than in the spectrum of mucilage control film and shift of C[dbnd]O stretching vibration peak lower wave number and widen in the mucilage films including cellulose nanofibers. Cellulose nanofibers did not reveal a significant effect on the thermal properties of the all three composite films and dynamic thermogravimetric values were recorded as ≃287 °C. Atomic force microscopy revealed a homogenous distribution of cellulose nanofibers across the mucilage matrix. Dynamic mechanical analysis revealed that the inclusion of cellulose nanofibers in mucilage film led to an enhancement of the tensile modulus as well as the tensile strength, but without reducing the strain at break of the film. Cellulose nanofibers incorporation significantly enhanced the hydrophobic properties of the composite films. The cytotoxicity assay results demonstrated mucilage composite films were nontoxic and have anticancer properties; reducing the viability of cancer cell line by ≃ 20% and retaining the cell viability of epithelial cell line by ≃ 90%. Cellulose nanofibers incorporation also significantly enhanced the antioxidant and antimicrobial attributes of the mucilage composite films. Overall, the current study provided an idea regarding the biocompatible, non-toxic, highly antioxidative and antimicrobial biodegradable nature of mucilage-CNF composite films, making it a suitable candidate for food and pharmaceutical industry.