Preparation and properties of nanoparticles modified fish scale gelatin-agar composite films silver

Tilapia fish scale gelatin (shortened to fish scale gelatin), as reducing agent and stabilizer was used to prepare silver nanoparticles (Ag NPs). The obtained Ag NPs were mixed with fish scale gelatin aqueous solution and agar aqueous solution to prepare fish scale gelatin-agar composite films with silver content 0.04%~0.19% (based on the total mass of fish scale gelation and agar, the same below). Ag NPs were characterized by UV-Vis, TEM and XRD. The effect of silver content on the physicochemical and antibacterial properties of gelatin-agar composite films was investigated. The results showed that Ag NPs were spherical and homogeneous with an average particle size of (9.3±1.8) nm. With the increase of silver content, the color of fish scale gelatin-agar composite film deepened and the transparency decreased. While the elongation at break, water-resistance and water vapor barrier properties significantly enhanced, the thickness and tensile strength had no obvious changes. FTIR and TG results indicated that there was chemical interaction between Ag NPs and film matrix, which results in the improvement of thermal stability of the composite film to some extent. Furthermore, the composite films could achieve good antibacterial effect at low silver contents (0.04%~0.19%). © 2020, Editorial Office of FINE CHEMICALS. All right reserved.