Metal‐Phenolic Networks Enable Biomimetic Antioxidant Interfaces Through Nanocellulose Engineering

Metal-phenolic networks (MPNs) integrated with functionalized cellulose nanofibers present a promising platform for stabilizing oxidation-sensitive compounds. Here, a novel antioxidant pickering emulsion system utilizing MPN-decorated carboxyl-functionalized pulp cellulose nanofibers (MPN-PCNF) is demonstrated. The system exhibits exceptional interfacial stability through synergistic effects of MPN coating and alkyl functionalization, validated by DLVO theoretical modeling and rheological characterization. MPN-PCNF demonstrates remarkable antioxidant efficacy, achieving 94% α-tocopherol retention over 50 days and 80% reduction in cellular reactive oxygen species. In reconstructed human skin models, the system significantly attenuates UV-induced oxidative stress, evidenced by preserved stratum corneum integrity and suppressed matrix metalloproteinase-1 expression. This biocompatible platform represents a versatile solution for protecting oxidation-sensitive compounds across pharmaceutical, cosmetic, and food applications, offering a sustainable alternative to conventional synthetic antioxidant systems.