Macroporous microbeads containing apatite-modified mesoporous bioactive glass nanofibres for bone tissue engineering...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Nanotechnology

Background:

• Mesoporous bioactive glass (MBG) offers enhanced surface area and pore volume compared to conventional bioactive glass, making it suitable for drug delivery.
• Fabrication of MBG as microbeads offers greater flexibility for filling various cavities compared to blocks.
• Fibrous materials and macroporous structures promote cell attachment, differentiation, and tissue ingrowth, mimicking the natural extracellular matrix.

Purpose of the Study:

• To fabricate macroporous microbeads incorporating mesoporous bioactive glass nanofibers (MMBs).
• To evaluate the cellular attachment, viability, and osteogenic potential of MMBs for bone tissue engineering applications.

Main Methods:

• Macroporous microbeads containing MBG nanofibers were fabricated using poly(methyl methacrylate) microspheres as sacrificial templates.
• Scanning electron microscopy and micro-computed tomography were used to characterize the porous structure of the MMBs.
• MG63 osteoblast-like cells were cultured on MMBs and glass beads to assess cellular attachment and viability. MMBs were subsequently modified with an apatite layer via simulated body fluid immersion.

Main Results:

• SEM and micro-CT confirmed the macroporous structure of the fabricated MMBs.
• Significantly higher cellular attachment was observed on MMBs compared to glass beads after 4 hours.
• Initial high calcium ion release reduced cell viability after 1 day; apatite modification (Ap-MMBs) mitigated this, improving viability.
• Animal studies demonstrated that Ap-MMBs significantly promoted new bone formation in bone defects compared to the control group.

Conclusions:

• Fabricated macroporous microbeads containing MBG nanofibers show promise for bone tissue engineering.
• Apatite modification of MMBs is crucial for enhancing cell viability by controlling calcium ion release.
• Ap-MMBs exhibit significant osteogenic potential, effectively promoting bone regeneration in vivo.