Bimetallic Ag+/Cr3+ and curcumin-encapsulated metal-organic frameworks: A triple-therapeutic synergistic strategy for enhanced antibacterial activity and infected wound healing

Wound healing in skin infections is frequently compromised by multi-drug-resistant bacterial colonization, persistent inflammation, and bacterial biofilm formation. To address these issues, we engineered an innovative multifunctional biomaterial (Cur@MIL-101(Cr/Ag)) which integrates potent antibacterial, anti-biofilm, and tissue-regenerative properties. This composite was constructed via a bimetallic synergistic and molecularly confined strategy, where Ag + and Cr 3+ were co-anchored within a terephthalic acid-based framework (MIL-101) through hydrothermal method, followed by the in situ encapsulation of curcumin. In vitro evaluations revealed potent broad-spectrum antibacterial activity against both Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli ), along with significant inhibition of biofilm formation and minimum inhibitory concentrations (MICs) of 8 ppm and 2 ppm, respectively. In vivo, topical application of Cur@MIL-101(Cr/Ag) in a wound-infected mouse model further demonstrated complete bacterial eradication, mitigated inflammatory responses, accelerated wound closure, and promoted tissue regeneration with no observable systemic toxicity within the scope of assessment (i.e., stable body weight and non-pathological organ morphology). The therapeutic efficacy can be attributed to a synergistic triple-therapy mechanism comprising: (i) electrostatic interaction, (ii) ROS-mediated oxidative stress induction, (iii) synergistic interaction of multiple antimicrobial components (Ag⁺, Cr³⁺, and curcumin). This nanoengineered platform presents a clinically translatable strategy for precision therapy of infected wounds, combining antimicrobial robustness, biofilm penetration, and pro-regenerative functions within an integrated therapeutic system.