Physico-mechanical and antimicrobial properties of tragacanth/hydroxypropyl methylcellulose/beeswax edible films reinforced with silver nanoparticles.

Abstract The novel trinary bio-composite film based on Tragacanth/Hydroxypropyl methylcellulose/Beeswax reinforced silver nanoparticles (AgNPs) was developed. This study investigated the effect of AgNPs (2, 4 and 8%) on some physico–mechanical and antimicrobial properties of bio-composite film. It was discovered that AgNPs reduced the composite tensile strength from 33.64 to 16.12 MPa. However, water vapor permeability was improved by addition of the nanoparticles (4.57–2.16 × 10−13 g m/m2 s Pa). The use of AgNPs influenced the apparent color of bio-composite film. The microscopic surface structure and topography of the films were also examined by scanning electron microscopy and Fourier transform infrared, respectively. Dynamic mechanical thermal analysis results showed that the thermal stability of film was slightly decreased through incorporation with AgNPs. Finally, nano-composite films demonstrated strong antibacterial activity against tested pathogen bacteria in the contact surface zone. The antimicrobial results suggest that new nanocomposite film may be used as food active packaging. Highlights • The mechanical resistance of the film decreased slightly by adding AgNPs. • Thermal stability of silver nano-composite film was slightly decreased through incorporation with AgNPs. • FT-IR analysis exhibited no chemical bonding between biopolymer and AgNPs. • Nano-composite films demonstrated strong antibacterial activity against tested pathogen bacteria. [ABSTRACT FROM AUTHOR]