A multifunctional nanocomposite hydrogel with controllable release behavior enhances bone regeneration

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Nanotechnology

Background:

• Autologous and allogeneic bone grafts are standard but face donor limitations and infection risks.
• Tissue engineering offers novel in situ bone repair strategies using bioactive composites.
• Developing advanced materials is crucial for overcoming current bone defect treatment limitations.

Purpose of the Study:

• To construct multifunctional nanocomposite hydrogels for enhanced bone defect repair.
• To investigate the synergistic osteogenic and antibacterial effects of the developed hydrogel.
• To evaluate the in vitro and in vivo efficacy of the hydrogel in promoting bone regeneration.

Main Methods:

• Covalently bound silver (Ag+) core-embedded mesoporous silica nanoparticles (Ag@MSN) to bone morphogenetic protein-2 (BMP-2).
• Encapsulated Ag@MSN-BMP-2 into silk fibroin methacryloyl (SilMA) and photo-crosslinked to form Ag@MSN-BMP-2/SilMA hydrogel.
• Assessed hydrogel biocompatibility, sustained-release properties, and bone regeneration in a rat skull defect model.

Main Results:

• The Ag@MSN-BMP-2/SilMA hydrogel demonstrated good biocompatibility and controlled sustained release of BMP-2.
• The hydrogel exhibited synergistic antibacterial and osteogenic effects, promoting bone defect repair.
• In vivo studies showed enhanced bone regeneration, osteogenic differentiation, and neovascularization in rat skull defects.

Conclusions:

• Ag@MSN-BMP-2/SilMA hydrogels represent a promising strategy for bone regeneration.
• The multifunctional hydrogel effectively addresses challenges associated with traditional bone grafts.
• This technology holds significant potential for advancing bone defect treatment and repair.