Development of a magnetic xanthan gum-polyacrylamide hydrogel embedding Cu-BTC with antibacterial properties for...

The design of multifunctional hydrogel platforms with strong antibacterial and pro-healing activity is essential for next-generation wound dressings. In this work, a novel nanocomposite hydrogel was fabricated by grafting polyacrylamide onto xanthan gum, crosslinking with borax, incorporating Fe₃O₄ nanoparticles, and inducing in-situ growth of Cu-BTC MOF within the magnetic hydrogel matrix. This integrated structure represents an efficient innovation among MOF-hydrogel systems by combining the biocompatibility of XG, the functional network provided by PAAm, the magnetic features of Fe₃O₄, and the controlled Cu²⁺-based antibacterial activity of Cu-BTC. Characterization confirmed successful formation and stable polymer-MOF interactions, accompanied by favorable physicochemical properties including superparamagnetic behavior (saturation magnetization ∼8 emu/g), relatively high surface area (56.90 m²/g), and improved thermal stability. The biological assessments were assessed for wound-healing relevance. Swelling of the hydrogels was measured at different pH values (4.0, 5.5, 7.4) and in varying ionic strengths, showing the highest uptake for XG-grafted-PAAm, while Fe₃O₄ and Cu-BTC reduced swelling by increasing crosslinking, supporting moisture retention and compact structure in wound environments. Furthermore, the magnetic XG-grafted-PAAm @Cu-BTC nanocomposite showed antibacterial activity, with MIC/MBC values of 125/250 μg/mL against E. coli and 500/1000 μg/mL against S. aureus. Cytocompatibility testing revealed acceptable viability at low-moderate concentrations (91-54% at 1.9-15.6 μg/mL), while the scratch assay confirmed accelerated fibroblast migration at 3.9 μg/mL, indicating a pronounced pro-healing effect. Overall, the synergistic antibacterial action, controlled Cu²⁺ release, hydration capacity, and favorable cell-migration response position this MOF-magnetic hydrogel system as a promising candidate for advanced wound dressings.