Autonomous, temperature-enhanced oxidase-mimic multimodal antimicrobial film for prolonged preservation of perishable products

Abstract

Confronting the escalating challenges of food waste and safety, primarily attributed to microbial-induced spoilage, this investigation unveils a cutting-edge nanozyme-based antimicrobial packaging paradigm with self-activating mechanism (CMn0.20-CS film), employing low-thermal aid to optimize the preservation of fruits and vegetables. At its core, the system amalgamates a carbon nanotube-supported Mn3O4 (CMn) filler within a chitosan (CS) film matrix. The fabrication of the CMn complex involves a dual-stage process, initially focusing on the immobilization of Mn2+ ions, followed by the wet chemical nucleation of Mn3O4 crystals. A pivotal feature of this construct is the weak acidity of CS matrix, which imparts the CMn0.20-CS film with a self-activating capacity, facilitating an optimal environment for the manifestation of oxidase-like activity. The CMn0.20-CS film exhibits a synergistic antimicrobial efficacy, derived from the augmented oxidase-mimetic and photothermal characteristics of CMn, in conjunction with the intrinsic microbial capture and killing capabilities of CS. This translates into formidable bactericidal proficiency (exceeding 99.99 % for bacteria and 99.67 % for mold), swift action (within 10 min), and a requirement for minimal auxiliary heat (56.4 ℃). Based on this, the CMn0.20-CS film significantly prolongs the shelf life of kumquats, extending its shelf life by 2.3 times. The augmented mechanical strength, improved barrier qualities, and demonstrated safety profile of the film underscore its potential for practical applications. Collectively, the CMn0.20-CS film stands out as an exceptionally suitable method for the effective preservation of perishable goods, tackling fundamental concerns in food safety and wastage mitigation.