3D-Printed Gentamicin-Releasing Poly-ε-Caprolactone Composite Prevents Fracture-Related Staphylococcus aureus...

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Infectious Disease Research

Background:

• Bacterial infections pose a significant risk in orthopedic and trauma surgery.
• Local antibiotic delivery enhances bone site concentration and minimizes toxicity compared to systemic administration.
• A need exists for personalized biomaterial-antibiotic combinations for patient-specific implants.

Purpose of the Study:

• To develop a novel composite coating for bone fixation plates using poly-ε-caprolactone, hydroxyapatite, and halloysite nanotubes.
• To load the composite with gentamicin sulfate for enhanced infection prevention.
• To fabricate the coated plates using fused filament fabrication 3D printing technology for patient-specific applications.

Main Methods:

• Fabrication of a poly-ε-caprolactone, hydroxyapatite, and halloysite nanotube composite via 3D printing.
• Loading the composite with varying concentrations of gentamicin sulfate.
• In vitro release kinetics analysis of gentamicin sulfate over 14 days.
• Evaluation of antimicrobial efficacy against Staphylococcus aureus in ex vivo and in vivo mouse models.

Main Results:

• The composite demonstrated favorable mechanical and thermal properties.
• In vitro studies showed an initial burst release followed by sustained release of bactericidal gentamicin concentrations.
• Complete eradication of Staphylococcus aureus was achieved in an ex vivo mouse femur infection model with 2% and 5% gentamicin sulfate loading.
• In vivo studies demonstrated that the 5% gentamicin sulfate-loaded plate prevented Staphylococcus aureus infection in bone and surrounding tissues.

Conclusions:

• The developed 3D-printed composite coating effectively prevents bacterial infection in vivo.
• This patient-specific implantable material offers a promising personalized solution for reducing surgical site infections in orthopedic procedures.
• Fused filament fabrication enables the creation of tailored implants, addressing limitations in current biomaterial-antibiotic combinations.