Bioinspired Composite Matrix Containing Hydroxyapatite-Silica Core-Shell Nanorods for Bone Tissue Engineering.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Nanotechnology

Background:

• Advancing bone tissue engineering requires multifunctional scaffolds that promote vascularization and regeneration.
• Hydroxyapatite (HA)-silica core-shell nanostructures offer potential for enhanced bone healing.
• Developing biocompatible materials is crucial for successful tissue regeneration.

Purpose of the Study:

• To develop and evaluate a novel composite scaffold incorporating hydroxyapatite (HA)-silica core-shell nanorods for bone tissue engineering.
• To assess the scaffold's biocompatibility, osteogenic differentiation, vascularization, and bone regeneration capabilities.
• To investigate the effect of silica incorporation on scaffold performance in vitro and in vivo.

Main Methods:

• Fabrication of hydroxyapatite (HA)-silica core-shell nanorods (Si-nHA) and their incorporation into a gelatinous matrix to form porous scaffolds.
• Characterization of Si-nHA using high-resolution transmission electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy.
• In vitro assessment of cell viability and functionality (mesenchymal stem cells and endothelial cells) and in vivo evaluation in chicken chorioallantoic membrane and rat femoral defect models.

Main Results:

• The Si-nHA nanorods possessed a crystalline HA core and amorphous silica sheath, retaining individual component characteristics.
• Scaffolds incorporating Si-nHA significantly improved the viability and functionality of osteogenically induced mesenchymal stem cells and endothelial cells.
• In vivo studies demonstrated good biocompatibility, enhanced vascularization compared to silica-free matrices, and significant new bone formation in a critical-sized femoral defect in rats.

Conclusions:

• The developed composite biomimetic scaffold containing hydroxyapatite (HA)-silica core-shell nanorods exhibits excellent biocompatibility and promotes both vascularization and bone regeneration.
• The incorporation of silica enhances the osteogenic and angiogenic potential of the scaffold.
• This novel nanocomposite scaffold represents a promising candidate for future bone tissue engineering applications.