Construction of a bioactive copper-based metal organic framework-embedded dual-crosslinked alginate hydrogel for antimicrobial applications

Int J Biol Macromol. 2023 Jul 1;242(Pt 1):124840. doi: 10.1016/j.ijbiomac.2023.124840. Epub 2023 May 9.

Abstract

Metal-organic frameworks (MOFs) containing bioactive metals have the potential to exhibit antimicrobial activity by releasing metal ions or ligands through the cleavage of metal-ligand bonds. Recently, copper-based MOFs (Cu-MOFs) with sustained release capability, porosity, and structural flexibility have shown promising antimicrobial properties. However, for clinical use, the controlled release of Cu2+ over an extended time period is crucial to prevent toxicity. In this study, we developed an alginate-based antimicrobial scaffold and encapsulated MOFs within a dual-crosslinked alginate polymer network. We synthesized Cu-MOFs containing glutarate (Glu) and 4,4'-azopyridine (AZPY) (Cu(AZPY)-MOF) and encapsulated them in an alginate-based hydrogel through a combination of visible light-induced photo and calcium ion-induced chemical crosslinking processes. We confirmed Cu(AZPY)-MOF synthesis using scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, and thermogravimetric analysis. This antimicrobial hydrogel demonstrated excellent antibacterial and antifungal properties against two bacterial strains (MRSA and S. mutans, with >99.9 % antibacterial rate) and one fungal strain (C. albicans, with >78.7 % antifungal rate) as well as negligible cytotoxicity towards mouse embryonic fibroblasts, making it a promising candidate for various tissue engineering applications in biomedical fields.

Keywords: Antimicrobial agent; Dual-crosslinking hydrogel; Metal organic framework.

MeSH terms

  • Alginates / chemistry
  • Animals
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Antifungal Agents
  • Copper* / chemistry
  • Fibroblasts
  • Hydrogels / chemistry
  • Metal-Organic Frameworks* / pharmacology
  • Metals
  • Mice

Substances

  • Copper
  • Metal-Organic Frameworks
  • Alginates
  • Hydrogels
  • Antifungal Agents
  • Anti-Bacterial Agents
  • Metals