Gallium-containing phospho-silicate glasses: synthesis and in vitro bioactivity

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Bioceramics

Background:

• Bioglass 45S5 is a well-established bioactive glass.
• Incorporating therapeutic ions into bioactive glasses is a key strategy for developing advanced biomaterials.
• Gallium is known for its antimicrobial properties and potential therapeutic effects.

Purpose of the Study:

• To synthesize and characterize gallium-containing phospho-silicate glasses based on Bioglass 45S5.
• To evaluate the bioactivity (hydroxyapatite formation) and ion release profiles of these glasses in simulated body fluid (SBF).
• To assess the safety and potential antimicrobial applications of gallium-doped bioactive glasses.

Main Methods:

• Fusion method for glass synthesis.
• Immersion in simulated body fluid (SBF) for 30 days.
• X-ray diffraction (XRD) and electronic scanning microscopy (ESM) for characterization.
• Inductively coupled plasma atomic emission spectrometry (ICP-AES) for ion release analysis.

Main Results:

• All synthesized gallium-containing glasses demonstrated hydroxyapatite (HA) formation in SBF.
• A stable HA layer formed rapidly (within 1 day) on glasses with up to 1.6% Ga2O3.
• Gallium was released and partially precipitated as gallium phosphate, with concentrations below toxic levels.
• Increased gallium content reduced overall ion release but maintained bioactivity.

Conclusions:

• Gallium-doped Bioglass 45S5 retains bioactivity and promotes HA formation.
• The released gallium is at non-toxic levels and may impart antimicrobial properties.
• These gallium-containing glasses are promising candidates for bioactive materials with enhanced therapeutic potential.