Functional enhancement of hydroxypropyl cellulose-based bionanocomposite films incorporating chitosan nanoparticles

The aims of the present study were to investigate the effect of the incorporation of chitosan nanoparticles (ChiNPs) on the physicochemical properties and antifungal activity of hydroxypropyl cellulose (HPC) bionanocomposite films. The films of 4% HPC and ChiNP at various dosages (0%, 0.1%, 0.5%, 1%, 1.5%, 3% w/w of HPC) were prepared. Atomic force microscopy (AFM) verified the dispersion of spherical-shaped ChiNP in a nanoscale size range (14.75–56.74 nm). Incorporation of nanofiller affected the functional properties by increasing the film–water contact angle to >53°, improving the optical properties, and reducing water vapour permeability by 5.73–12.54%. These results were influenced by surface roughness and microstructure characteristics of a bionanocomposite film, which were confirmed using AFM and scanning electron microscopy (SEM). Tensile assays of the films showed slight increases in tensile strength from 8.87 to 11.08 MPa and Young's modulus from 0.10 to 0.15 GPa with increasing proportions of ChiNP (1.5%). An effective concentration of ChiNP of 1.5% (w/w of HPC) was able to improve the performance of HPC and offered antifungal activity against Botrytis cinerea, as confirmed through mycelial growth inhibition assays and by membrane integrity changes. The HPC/ChiNP bionanocomposite films may have potential applications for active packaging, particularly for fresh fruit commodities.