Synergistic Antimicrobial Packaging Film with Photothermal-Controlled Biocatalytic Capability for Tangerine Preservation

The nanomaterials-functionalized composite packaging film with antimicrobial performance has attracted more and more research interests. However, designing the multi-mode synergistic composite film for efficient and intelligent antibacterial is still a challenge. In this work, a Fe-MoO x functionalized chitosan composite film (CS/FM) was designed by doping the Fe-MoO x into chitosan film. CS/FM film inherited excellent photothermal performance and photothermal-enhanced oxidase-like activity of Fe-MoO x , which endow CS/FM film with superior antimicrobial ability. The optimal composite film (CS/FM 0.2 ) able to killed ≥98.87% of S. aureus and ≥98.26% of E. coli , and could significantly inhibit the growth of P. expansum and P. italicum . Besides, CS/FM 0.2 film also showed good water vapor permeability (0.71 × 10 −10 g m −1 s −1 Pa −1 ) and tensile strength (58.16 MPa). Low hemolysis rate (≤ 4.91%), high cell viability (≥ 90.32%), and the normal body organs after being treated with Fe-MoO x verified the biosafety of CS/FM film. The tangerine preservation results indicated that CS/FM 0.2 film could extend the shelf life of tangerine by at least 9 days and prevent the loss of tangerine nutrients. Our work boosted the development of designing composite packaging film with multi-mode synergistic antimicrobial effect via nanomaterials functionalized for food preservation.