Highly reactive crystalline-phase-embedded strontium-bioactive nanorods for multimodal bioactive applications

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Biomineralization

Background:

• Bioglass 45S5 is a well-established bioactive glass for bone regeneration.
• Crystallization can significantly alter the properties of bioactive glasses.
• Strontium substitution is explored to enhance bioactivity and antibacterial properties.

Purpose of the Study:

• To develop a crystallization-induced strontium-bioactive material using a sol-gel-assisted microwave method.
• To investigate the influence of induced crystallization on bioactivity and mechanical properties for bone and dentin regeneration.
• To evaluate the potential of strontium-substituted material for dentin regeneration applications.

Main Methods:

• Sol-gel-assisted microwave synthesis to produce nanorod-shaped bioactive material.
• X-ray diffraction (XRD) with Rietveld analysis to identify crystalline phases.
• Multinuclear solid-state Nuclear Magnetic Resonance (NMR) spectroscopy for atomistic insights.
• In vitro apatite formation studies and dentin matrix/antibacterial assays.
• Computational simulation studies to assess binding affinity with salivary compounds.

Main Results:

• A crystallization-induced strontium-bioactive material with nanorod morphology (30-80 nm) was successfully synthesized.
• XRD analysis identified sodium and calcium-enriched crystal systems, including sodium calcium silicate and calcium strontium silicate.
• Solid-state NMR confirmed the presence of crystalline mineral phases.
• 5% strontium substitution demonstrated enhanced antibacterial properties and higher binding affinity to salivary compounds, suitable for dentin regeneration.
• In vitro apatite formation confirmed suitability for bone regeneration.

Conclusions:

• The sol-gel microwave method yields a crystallization-induced strontium-bioactive material with tunable properties.
• The crystallized material exhibits excellent bioactivity and mechanical properties beneficial for bone regeneration.
• Strontium substitution enhances antibacterial effects and salivary compound binding, indicating strong potential for dentin regeneration applications.