Fabrication of an Intelligent Thin Film Functionalized with MSAL-BTR Composite Nanoparticles for Real-Time Food Freshness Monitoring

This paper reports the development of a novel intelligent film for food freshness monitoring. The material is composed of a poly(vinyl alcohol) (PVA) matrix functionalized with pH-responsive methyl methacrylate-shikonin-allicin (MSAL) composite nanoparticles loaded with betaine (BTR). Fabricated via a straightforward solution blending and casting process, the resulting MSAL-BTR-PVA film demonstrates a dual pH-responsive colorimetric and fluorometric change, coupled with high stability and sensitivity. The microstructure and antibacterial properties of the MSAL-BTR-PVA film were investigated. These properties establish its significant potential for application as an intelligent packaging material capable of real-time food quality assessment.