A Novel Chitosan-Modified PLA Doped n-HA Bone Scaffold.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Orthopedic Research

Background:

• Polylactic acid (PLA) bone scaffolds degrade into acidic byproducts, potentially hindering bone regeneration.
• Chitosan (CS) offers hydrophilicity, bacteriostasis, and alkalinity, while nano-hydroxyapatite (n-HA) enhances osteogenic properties.
• Developing advanced bone scaffolds requires addressing degradation issues and improving biocompatibility and bioactivity.

Purpose of the Study:

• To synthesize and characterize a novel polylactic acid-chitosan/nano-hydroxyapatite (PLA-CS/n-HA) composite bone scaffold.
• To evaluate the effects of CS and n-HA incorporation on PLA scaffold properties, including hydrophilicity, mechanical strength, and degradation behavior.
• To assess the in vitro biocompatibility, osteogenic potential, and antibacterial activity of the developed PLA-CS/n-HA bone scaffold.

Main Methods:

• Synthesis of PLA-CS graft via ferulic acid-mediated grafting of CS onto PLA.
• Fabrication of PLA-CS/n-HA bone scaffolds incorporating nano-hydroxyapatite.
• Characterization of scaffold properties: hydrophilicity, compressive strength, and antibacterial efficacy against Staphylococcus aureus and Escherichia coli.
• In vitro cell culture studies using MC3T3-E1 cells to assess cell adhesion, proliferation, differentiation, and alkaline phosphatase activity.
• Cytotoxicity assessment of the PLA-CS/n-HA bone scaffold.

Main Results:

• The PLA-CS/n-HA bone scaffold exhibited enhanced hydrophilicity and compressive strength compared to pure PLA scaffolds.
• The scaffold demonstrated significant antibacterial activity, particularly against Staphylococcus aureus.
• MC3T3-E1 cell adhesion rate reached 118.95% after 12h co-culture, with preliminary differentiation and elevated alkaline phosphatase activity (1.23) after 14 days.
• Acidity from PLA degradation was alleviated in the PLA-CS/n-HA scaffold.
• The scaffold received a cytotoxicity grade of class 0, indicating excellent biocompatibility.

Conclusions:

• The developed PLA-CS/n-HA bone scaffold effectively enhances hydrophilicity, mechanical strength, and antibacterial properties.
• The incorporation of CS and n-HA promotes new bone formation and tissue attachment while mitigating acidic degradation products.
• The PLA-CS/n-HA scaffold shows promising potential for bone tissue engineering applications due to its biocompatibility and osteogenic capabilities.