Vancomycin- and Poly(simvastatin)-Loaded Scaffolds with Time-Dependent Development of Porosity.

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Tissue Engineering

Background:

• Biodegradable scaffolds are crucial for tissue engineering and drug delivery.
• Current scaffolds often lack the ability to deliver multiple therapeutic agents effectively.

Purpose of the Study:

• To develop novel biodegradable scaffolds capable of dual drug delivery for enhanced bone tissue regeneration.
• To create a scaffold matrix that controls the release of angiogenic, osteogenic, and antibacterial agents.

Main Methods:

• Fabrication of scaffolds using poly(simvastatin) in poly(β-amino ester) (PBAE) porogens and vancomycin-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres.
• Controlled porosity development via PBAE porogen degradation.
• In vitro release studies for simvastatin acid and vancomycin.
• Bioactivity assays to assess simvastatin acid efficacy.
• Mechanical property testing (compressive modulus, failure strain, failure stress).

Main Results:

• Scaffolds demonstrated controlled release of simvastatin acid (up to ~162 μg) and vancomycin (up to ~18 mg).
• Higher porogen loading (~60%) resulted in ~70% interconnected porosity (~180 μm pore spacing), facilitating drug release.
• Released simvastatin acid showed bioactivity, stimulating preosteoblastic activity.
• Mechanical properties decreased with increased porogen content.

Conclusions:

• The developed biodegradable scaffolds offer a dual drug delivery system with tunable microarchitecture.
• These scaffolds show significant potential for applications in bone tissue engineering due to controlled drug release and bioactivity.
• The fabrication method allows for simultaneous delivery of agents promoting bone formation and preventing infection.