Photothermal Hydrogel Encapsulating Intelligently Bacteria-Capturing Bio-MOF for Infectious Wound Healing

Abstract

Chronic wounds are characterized by long-term inflammation and persistent infection, which make them difficult to heal. Therefore, an urgent desire is to develop a multifunctional wound dressing that can prevent wound infection and promote wound healing by creating a favorable microenvironment. In this study, a curcumin-based metal–organic framework (QCSMOF-Van), loaded with vancomycin and coated with quaternary ammonium salt chitosan (QCS), was prepared. Multifunctional composite hydrogels were conveniently synthesized by combining methacrylic anhydride modified gelatin and methacrylic anhydride modified oxidized sodium alginate with QCSMOF-Van through radical polymerization and Schiff base reaction. It is important to note that the QCSMOF-Van could capture bacteria through the positive charges on the surface of QCS. In this process, due to the synergistic effect of broad-spectrum antibacterial Zn2+ and vancomycin, the metabolism of bacteria was well inhibited, and the efficient capturing and rapid killing of bacteria were achieved. The QCSMOF-Van hydrogels could precisely regulate the balance of M1/M2 phenotypes of macrophages, thereby promoting the regeneration of nerves and blood vessels, which promotes the rapid healing of chronic wounds. This advanced cascade management strategy for tissue regeneration highlights the potential of multifunctional composite hydrogels in chronic wound dressings.

A Gelatin-Based Composite Hydrogel with a “One Stone, Two Birds” Strategy for Photothermal Antibacterial and Vascularization of Infected Wounds

“…The experimental results showed that the introduction of Fe-BGs could effectively activate the angiogenic ability, and the therapeutic effect could be further enhanced by combining with NIR radiation, which has a certain “hot spring effect” . It is worth noting that there are abundant skin nerves under the skin, and when the wound is damaged, the nerves will also be destroyed . Previous studies have shown that angiogenesis is essential for nerve regeneration and neurovascular interactions play a considerable role in wound healing .…”

“…56 It is worth noting that there are abundant skin nerves under the skin, and when the wound is damaged, the nerves will also be destroyed. 57 Previous studies have shown that angiogenesis is essential for nerve regeneration and neurovascular interactions play a considerable role in wound healing. 58 As shown in Figure S5, compared with the control group, the relative coverage area of β3-tubulin in the GTB0, GTB5, and GTB5 + NIR groups increased by 1.38,1.89, and 1.19 times, respectively.…”

Recent progress of antibacterial hydrogels in wound dressings

“…prepared hydrogel dressings by combining methacrylic anhydride-modified gelatin and modified oxidized sodium alginate with a metal-based organic backbone. The hydrogel inhibited bacterial metabolism by loading vancomycin [ 201 ]. Vancomycin is a glycopeptide antibiotic that interferes with bacterial cell wall synthesis by disrupting peptidoglycan.…”

A cooling-driven self-adaptive and removable hydrogel coupled with combined chemo-photothermal sterilization for promoting infected wound healing

“…The local heat generated by the NIR laser (808 nm) can effectively eliminate bacteria, reduce inflammation, and further speed up wound healing in PTT. [33][34][35] The use of materials with excellent photothermal properties will facilitate the reduction of laser power density, minimizing tissue damage. Thus, the photothermal ability of the rGO@PDA/Ag-PF127 hydrogels was investigated by irradiating the hydrogel samples with an NIR laser (808 nm, 0.45 W cm −1 ).…”