Injectable Magnesium-Zinc Alloy Containing Hydrogel Complex for Bone Regeneration

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Engineering

Background:

• Gelatin methacryloyl (GelMA) is used in bone engineering but lacks osteoinductive capacity for calvarial defects.
• Injectable hydrogels offer potential for repairing irregular calvarial defects.

Purpose of the Study:

• To develop an injectable magnesium-zinc alloy containing hydrogel complex (Mg-IHC) for enhanced bone regeneration.
• To evaluate the osteogenic potential and efficacy of Mg-IHC in calvarial defect repair.

Main Methods:

• Fabrication of magnesium-zinc alloy spheres via atomization process.
• Characterization of Mg-IHC properties, including injectability, mechanical modulus, and biocompatibility.
• In vitro assessment of osteogenic differentiation using MC3T3-E1 cells (ALP activity, staining, gene expression).
• In vivo evaluation of Mg-IHC in a mouse model of critical-sized calvarial defect.

Main Results:

• Mg-IHC exhibited good fluidity, injectability, and plastic shaping capabilities.
• The hydrogel complex demonstrated excellent biocompatibility and promoted cell adhesion, growth, and proliferation.
• Mg-IHC significantly enhanced osteogenic differentiation of cells and upregulated key bone formation markers (ALP, COL-I, OCN, RUNX2).
• In vivo studies showed remarkable bone formation enhancement in calvarial defects treated with Mg-IHC.

Conclusions:

• Mg-IHC is a promising injectable biomaterial for calvarial defect repair.
• The material effectively promotes osteogenic differentiation and bone regeneration.
• Mg-IHC represents a potential advancement in materials for orthopedic and regenerative applications.