Synergistic organic-inorganic hybridization of PEG-functionalized CuFe₂O₄ spinel nanoparticles within cellulose acetate/gelatin films for enhanced structural stability and antimicrobial efficacy.

This study reports the green synthesis, PEG functionalization, and polymeric integration of CuFe₂O₄ nanoparticles into a cellulose acetate/gelatin (CA/Gel) matrix for advanced biomedical applications. The Piper betle-mediated synthesis produced nanocrystalline CuFe₂O₄ with a spinel structure, confirmed by XRD and FTIR, while FESEM and TEM analyses revealed spherical particles with sizes ranging from 20 to 80 nm and inherent agglomeration due to magnetic dipole interactions. PEG functionalization significantly improved dispersion stability through steric hindrance and hydration layer formation, as evidenced by reduced aggregation, increased hydrodynamic size, and enhanced zeta potential. Mechanistically, the phytochemical-mediated nucleation and growth of CuFe₂O₄ nanoparticles are driven by polyphenol-assisted metal ion chelation and controlled oxidation, while PEG adsorption introduces steric repulsion and modifies interfacial energetics, suppressing magnetic clustering. Incorporation into the CA/Gel matrix resulted in a semi-interpenetrating polymer network stabilized by hydrogen bonding and electrostatic interactions, leading to enhanced morphological uniformity and improved thermal stability. The nanocomposite exhibited optimized wettability (67.1°), reduced swelling, and controlled moisture uptake, attributed to nanoparticle-induced restriction of polymer chain mobility and reduced free volume. Biologically, PEG-CuFe₂O₄ nanocomposites demonstrated improved hemocompatibility (<10% hemolysis) and enhanced antibacterial activity, particularly against Gram-positive strains, driven by synergistic mechanisms including reactive oxygen species (ROS) generation, Cu2+ ion release, and membrane disruption. The controlled degradation profile further supports its suitability for wound healing applications. The study establishes a structure-property-unction relationship, demonstrating that PEG-mediated interfacial engineering and nanoparticle-polymer interactions are key to tailoring physicochemical and biological performance in ferrite-based nanocomposites.