Synthesis of Fe3O4@SiO2@PAMAM dendrimer@AgNP hybrid nanoparticles for the preparation of carrageenan-based functional nanocomposite film

Fe3O4 nanoparticles were modified using polyamidoamine (PAMAM) dendrimer and the magnetic core-shell nanomaterials were decorated with silver nanoparticles (AgNPs) to prepare hybrid nanoparticles (HNPs) of Fe3O4@SiO2@PAMAM@AgNP. The HNPs were characterized using transmission electron microscopy (TEM), Xray diffraction analysis (XRD), and energy-dispersive X-ray spectroscopy (EDX). Various amounts (0, 0.5, 0.75, and 1.0 wt%) of the HNPs were used to prepare carrageenan-based nanocomposite films. SEM results showed that the HNPs (Fe3O4@SiO2@PAMAM@AgNP) were uniformly dispersed in the carrageenan films in the range of 0.5-1 wt% to form compatible nanocomposite films. Though the mechanical and water vapor barrier properties of carrageenan film were not influenced by the addition of the HNP, the carrageenan/HNP composite films exhibit high UV-barrier property and clear antibacterial activity against foodborne pathogenic bacteria, L. monocytogenes, and E. coli.