Hybrid Chitosan/PCL Shape Memory Scaffolds with Potential for Bone Regeneration and Infection Resistance

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Polymer Chemistry

Background:

• Craniomaxillofacial bone defects require advanced regenerative solutions.
• Existing poly(ε-caprolactone) (PCL) shape memory polymer (SMP) scaffolds have limitations in degradation rate and antimicrobial activity.
• Chitosan (CS) possesses inherent antimicrobial properties and biodegradability, making it a promising additive.

Purpose of the Study:

• To develop and characterize novel hybrid chitosan/poly(ε-caprolactone) (CS/PCL) SMP scaffolds.
• To evaluate the impact of chitosan incorporation on scaffold degradation, mechanical properties, and antimicrobial efficacy.
• To assess the potential of these hybrid scaffolds for enhanced bone tissue regeneration.

Main Methods:

• Fabrication of semi-interpenetrating network (semi-IPN) CS/PCL SMP scaffolds using PCL-diacrylate and CS-graft-PCL copolymers.
• Tuning scaffold properties by adjusting CS content via graft copolymer composition and PCL-DA ratio.
• Utilizing a solvent-cast particulate leaching method to create highly porous, interconnected macropores (∼240 μm).
• Assessing in vitro degradation rates, mechanical behavior, shape memory properties, and anti-biofilm activity against Candida albicans.

Main Results:

• Successfully synthesized hybrid CS/PCL SMP scaffolds with tunable CS content.
• Hybrid scaffolds exhibited faster in vitro degradation rates compared to PCL controls, attributed to increased hydrophilicity and phase separation.
• Scaffolds maintained excellent shape memory and robust mechanical properties due to retained PCL crystallinity.
• Hybrid scaffolds demonstrated significant reduction in Candida albicans biofilm formation.

Conclusions:

• Hybrid CS/PCL SMP scaffolds offer a promising advancement for craniomaxillofacial bone defect repair.
• The incorporation of chitosan enhances degradation profiles and provides crucial antimicrobial activity.
• These findings support the potential of CS/PCL SMP scaffolds to improve osteoinductivity and mitigate infection risks in regenerative applications.