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Updated: Jun 15, 2026
07:24
Preparation of Cross-Linked Sodium Alginate Microspheres with Different Metal Ions Using the Microfluidic Electrospray Technology
Published on: June 7, 2024
Bioactive inorganic-materials/alginate composite microspheres with controllable drug-delivery ability
Chengtie Wu1, Yufang Zhu, Jiang Chang
1Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane QLD 4059, Australia.
Summary
Incorporating bioactive materials like mesoporous bioglass into alginate microspheres significantly enhances drug loading and controls release for bone repair applications. These composite microspheres show improved bioactivity and degradation profiles.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Regenerative Medicine
Background:
- Alginate microspheres offer biocompatibility for bone repair but suffer from poor drug loading and uncontrolled release.
- Enhancing alginate microspheres with bioactive inorganic materials is crucial for improving their therapeutic potential.
Purpose of the Study:
- To evaluate the impact of incorporating mesoporous bioglass (MBG), nonmesoporous bioglass (BG), or hydroxyapatite (HAp) into alginate microspheres.
- To investigate the effects on drug (dexamethasone) loading capacity and release kinetics.
- To assess the bioactivity and degradation characteristics of the composite microspheres.
Main Methods:
- Composite microspheres (alginate with MBG, BG, or HAp) were fabricated.
- Characterization involved X-ray diffraction (XRD), electron microscopy (TEM, SEM), FTIR, and AES.
- Dexamethasone loading and release were quantified in phosphate-buffered saline (PBS) at varying pH.
Main Results:
- Incorporation of MBG, BG, and HAp enhanced drug-loading capacity, with MBG/alginate showing the highest efficiency.
- Dexamethasone release correlated with the dissolution of the inorganic components and was pH-dependent; higher pH increased release.
- Composite microspheres exhibited varied apatite formation and dissolution, indicating differential bioactivity and degradation.
Conclusions:
- Composite microspheres of alginate with MBG, BG, or HAp demonstrate improved drug delivery capabilities for bone tissue regeneration.
- The bioactivity and degradation profiles of these composites are significantly enhanced, making them promising bioactive filler materials.
- Controlled drug release, influenced by pH and material composition, is achievable for targeted bone repair therapies.
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