Surface modification of biodegradable porous Mg bone scaffold using polycaprolactone/bioactive glass composite

Area of Science:

• Biomaterials Science
• Orthopedic Engineering
• Materials Science

Background:

• Magnesium (Mg) and its alloys are promising for orthopedic implants due to their biocompatibility and biodegradability.
• However, rapid degradation limits their clinical application in bone repair.
• Surface modification is crucial to control degradation and enhance osseointegration.

Purpose of the Study:

• To develop a biocompatible coating for Mg scaffolds to improve their degradation resistance and bioactivity.
• To investigate the effect of polycaprolactone and bioactive glass (PCL-BG) composite coating on Mg scaffold properties.
• To assess the potential of PCL-BG coated Mg scaffolds as bone substitutes.

Main Methods:

• Mg scaffolds were coated with a polycaprolactone (PCL) and bioactive glass (BG) composite using dip-coating under low vacuum.
• Coated and uncoated scaffolds were characterized for bioactivity, mechanical integrity, and degradation behavior.
• Immersion in simulated body fluid (SBF) was used to evaluate apatite formation.

Main Results:

• PCL-BG coated Mg scaffolds demonstrated significantly enhanced bioactivity compared to uncoated scaffolds.
• The PCL-BG coating improved the mechanical integrity and delayed the degradation rate of the Mg scaffolds.
• Apatite layer formation on the coated scaffolds in SBF indicated good biocompatibility and potential for bone in-growth.
• Increased PCL-BG concentration (threefold) further improved degradation resistance and mechanical stability.

Conclusions:

• Polycaprolactone-bioactive glass (PCL-BG) composite coatings effectively enhance the bioactivity, mechanical stability, and degradation resistance of magnesium scaffolds.
• The PCL-BG coating promotes apatite formation, crucial for bone regeneration and implant longevity.
• PCL-BG is a promising material for surface modification of Mg scaffolds for orthopedic applications.