Biodegradable starch-based nanocomposite films with laser-synthesized silver nanoparticles: A materials approach for...

This study investigates the development of corn starch nanocomposite films containing silver nanoparticles (AgNPs) synthesized by ultra-short pulse Ti:Za laser (AgNP F) and compares them with films containing chemically synthesized AgNPs (AgNP in situ). AgNP F, formed in a 1 % w/v starch solution, exhibited a well-dispersed spherical morphology (3 nm radius), which was confirmed by UV-vis spectroscopy and TEM images. Both types of nanoparticles were successfully integrated into 3 % w/v starch film-forming suspensions, to obtain nanocomposite materials without structural defects, as observed by SEM. AgNP F films had an intense yellow hue compared to those with AgNPs in situ. The nanocomposite films exhibited improved mechanical, optical, and barrier properties, compared to the control starch films, which is critical for packaging applications. However, cytotoxicity assessments revealed that AgNP F films reduced Caco-2/TC7 cell viability to 66 %, whereas AgNP in situ films maintained 90 % viability. Both nanocomposite films affected the viability of Vero cells. These results demonstrate that AgNPs significantly improve the structural and functional properties of starch-based films, although biocompatibility is dependent on the synthesis method. This research advances biopolymer-based nanocomposites for sustainable packaging applications.