Antibacterial PLA/Mg composite with enhanced mechanical and biological performance for biodegradable orthopedic...

Area of Science:

• Biomaterials Science
• Orthopedic Engineering
• Polymer Composites

Background:

• Orthopedic implants require biodegradability, bone-healing capacity, and infection prevention.
• Polylactic acid (PLA) offers biodegradability but lacks mechanical strength and bioactivity.
• Magnesium (Mg) possesses good bioactivity, biodegradability, and mechanical properties, with inherent antibacterial photothermal effects.

Purpose of the Study:

• To fabricate an antibacterial Polylactic acid/Magnesium (PLA/Mg) composite for enhanced orthopedic implants.
• To improve mechanical strength, bioactivity, and introduce antibacterial properties to PLA using Mg.

Main Methods:

• Fabrication of PLA/Mg composites with 15 and 30 vol% Mg using a high-shear mixer.
• Evaluation of mechanical properties (compressive strength, stiffness).
• Assessment of biological performance (cell attachment, proliferation, differentiation) and antibacterial effects via photothermal stimulation.

Main Results:

• PLA/Mg composites showed significantly enhanced compressive strength (up to 107.3 MPa) and stiffness (up to 2.5 GPa) compared to pure PLA.
• 15 vol% Mg composite improved cell attachment and proliferation; 30 vol% Mg showed decreased proliferation due to rapid degradation.
• PLA/Mg composites demonstrated antibacterial activity, amplified by near-infrared (NIR) induced photothermal effects.

Conclusions:

• Antibacterial PLA/Mg composites offer superior mechanical and biological performance for biodegradable orthopedic implants.
• The 15 vol% Mg composite shows potential for enhanced bone healing and infection prevention.
• This composite material presents a promising candidate for future orthopedic applications.