Metal-phenolic network-stabilized resveratrol nanoparticles as antimicrobial platforms for fresh pork preservation

In this study, metal-phenolic network stabilized resveratrol (RES) nanoparticles are prepared via coordination-driven self-assembly between tannic acid (TA) and ferric ions (Fe³⁺) to enhance the stability and functionality of RES. The nanoparticles exhibit a uniform particle size (132.17 ± 2.38 nm), narrow size distribution (PDI 0.29 ± 0.02), good colloidal stability, and pH-responsive sustained-release behavior, along with high encapsulation efficiency (93.09 ± 0.59%) and loading efficiency (67.74 ± 1.47%). Antibacterial assays demonstrate that RES@TA-Fe nanoparticles display enhanced inhibitory activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), achieving complete inhibition of S. aureus at 4 μg/mL and significant suppression of E. coli at 40 μg/mL. Mechanistic analysis indicate that this antibacterial effect is caused by synergistic reactive oxygen species (ROS) generation, leading to oxidative stress-induced membrane damage, lipid peroxidation, and leakage of intracellular components. RES@TA-Fe nanoparticles are further incorporated into sodium alginate/carboxymethyl cellulose biopolymer films to develop active packaging materials. The films show reduced light transmittance, enhanced antioxidant activity, decreased water vapor and oxygen permeability, improved flexibility and limited component migration. Application tests using refrigerated pork demonstrate that the RES@TA-Fe-loaded films effectively delay quality deterioration, inhibit microbial growth, and extend shelf life. In addition, the preliminary cytocompatibility evaluation demonstrate that the composite films exhibit favorable biosafety under the tested conditions. This work presents a promising metal-phenolic network-based nanoplatform for developing safe, effective antimicrobial systems for fresh pork preservation.