Inhibiting Effects of Antibiotic-Loaded Porous Gelatin-Hydroxyapatite Microspheres on Staphylococcus aureus

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Orthopedic Surgery

Background:

• Calcium phosphate materials, particularly hydroxyapatite (HAp), are ideal for localized antibiotic delivery in bone regeneration due to their biocompatibility and bone-like properties.
• Bone infections pose a significant challenge, necessitating effective localized antibiotic delivery systems.

Purpose of the Study:

• To develop and evaluate HAp-based composite microspheres for controlled antibiotic release and antibacterial efficacy in treating bone infections.
• To assess the osteoconductive potential and biocompatibility of these microspheres for bone regeneration.

Main Methods:

• Uniform and porous hydroxyapatite-gelatin composite microspheres (G-HAM) were synthesized using a simple wet-chemical method.
• Four antibiotics (gentamicin, vancomycin, teicoplanin, zyvox) were incorporated, and their release profiles and antibacterial activity against *Staphylococcus aureus* were evaluated.
• Characterization included structural, morphological, compositional, and thermal stability analyses.

Main Results:

• G-HAM microspheres exhibited a porous structure suitable for drug delivery.
• An initial burst release of antibiotics was observed, followed by sustained release, with antibiotics containing carboxylic groups showing prolonged release due to stronger HAp interaction.
• Released antibiotics retained their bioactivity, and G-HAM promoted osteoblast-like cell adhesion and proliferation, demonstrating excellent biocompatibility.

Conclusions:

• Gelatin-HAp microspheres offer a promising platform for integrated, controlled antibiotic delivery and osteoconductive potential.
• This approach holds significant promise for treating bone infections and enhancing bone tissue regeneration.