Nanocellulose/FeO/Ag Nanozyme with Robust Peroxidase Activity for Enhanced Antibacterial and Wound Healing Applications.

Peroxidase memetic nanozymes with their free radical-mediated catalytic actions proved as efficacious antibacterial agents for combating bacterial resistance. Herein, nanocellulose (NC) extracted from straw was used to prepare NC/FeO/Ag peroxidase nanozyme as an antibacterial and wound healing agent. Characterization of the nanozyme with XRD, FTIR, SEM-EDX, and XPS confirmed the presence of silver NPs and the magnetite phase of iron oxide dispersed on nanocellulose. The peroxidase activity of the prepared nanozyme was examined using TMB and HO as substrates which turned blue in acidic pH (λ = 652 nm). With a lower (0.387 mM), the nanozyme showed a comparable affinity for TMB with that reported for the HRP enzyme. Furthermore, the nanozyme remained efficient over a broader temperature range while maintaining 61.53% of its activity after the fourth cycle. In vitro, antibacterial tests against (Gram-negative) and (Gram-positive) bacterial strains showed that NC/FeO/Ag exhibits concentration-dependent and enhanced antibacterial effect for compared to NC and NC-FeO and negative control. Furthermore, the wound-healing performance of the NC-FeO-Ag nanozyme was investigated in vivo using an animal model (mice). The nanozyme showed 30% higher wound healing performance compared to the control base ointment and is comparable with the commercial nitrofurazone ointment. The results show the potential of the prepared nanozyme for wound-healing purposes.