Synergistic Effects of Cellulose Nanofibers and Coinage Metal Nanoparticles (Ag, CuO, and ZnO) in Active Packaging Biocomposites

This study delves into the synthesis and characterization of cellulose nanofibers (NFCs) and their nanobiocomposites incorporating coinage nanoparticles ( Ag,ZnO, and CuO ). NFCs were derived from oil palm empty fruit bunches, yielding fibers with diameters below 5 nm. Silver nanoparticles were synthesized using a reduction method, resulting in spherical particles sized between 10-25 nm. The integration of these nanoparticles into the NFCs matrix was confirmed through SEM, TEM, FT-IR, and XRD analyses. FT-IR spectrum of cellulose nanofibers exhibited peaks at 3399 − 3164 cm^−1 for hydroxyl groups, 2925 − 2812 cm^−1 for the cellulose skeleton, and 1013 cm^−1 for the -C-O-C/-C-O-H group. Significant changes were observed in the spectrum post-nanoparticle addition, notably at 1412 and 1317 cm^−1. SEM analysis revealed microdomains of metallic nanoparticles dispersed within the cellulose nanofiber matrix, contributing to increased molecular orientation and crystallinity index. The crystallinity index of cellulose nanofiber films varied: NFC alone exhibited 76.27%, NFC − ZnO 78.54%, NFC-CuO 77.34%, NFC-Ag 76.29%, and NFC-All 77.95%. These variations directly impacted the mechanical properties of the nanobiocomposites, which exhibited significant improvements. Biological analysis confirmed antimicrobial efficacy against E. coli, S. aureus, and C. albicans due to the presence of metallic nanoparticles. Furthermore, water vapor permeability assessments concluded that the nanobiocomposites are suitable for food packaging applications. These findings underscore the promise of NFC-based nanobiocomposites with coinage nanoparticles for advanced packaging materials. Future research avenues should focus on optimizing nanoparticle loading, refining dispersion techniques, and exploring further applications for these versatile nanobiocomposites.