Solid-State Dewetting of Thin Au Films for Surface Functionalization of Biomedical Implants

Area of Science:

• Biomaterials Science
• Nanotechnology
• Orthopedic Surgery

Background:

• Biomaterial-centered infections pose a significant challenge for orthopedic implants.
• Aging populations and sedentary lifestyles exacerbate the risk of implant-associated infections.
• Improving implant osteointegration and combating infection are critical for patient outcomes.

Purpose of the Study:

• To develop a novel method for functionalizing titanium alloy (Ti-6Al-4V) implant surfaces.
• To create a surface capable of delivering anti-infective agents and promoting osteointegration.
• To demonstrate a versatile approach for conjugating antibiotics onto implant surfaces.

Main Methods:

• Fabrication of gold (Au) nanoparticles on Ti-6Al-4V using solid-state dewetting of a 5 nm Au film.
• Conjugation of the antibiotic vancomycin to the Au nanoparticle surface via a poly(ethylene glycol) linker.
• Characterization using high-resolution scanning electron microscopy (HR-SEM), atomic force microscopy (AFM), high-resolution scanning transmission electron microscopy (HR-STEM), and X-ray photoelectron spectroscopy (XPS).

Main Results:

• Equiaxed Au nanoparticles with a mean diameter of 19.8 ± 7.2 nm were successfully produced on the Ti-6Al-4V surface.
• Successful conjugation of vancomycin, forming an 18.8 ± 1.3 nm-thick film, was confirmed.
• The study established a link between the solid-state dewetting process and successful surface functionalization.

Conclusions:

• A novel, simple, and versatile method for functionalizing medical implant surfaces was demonstrated.
• The developed technique enables the attachment of anti-infective agents to implant materials.
• This approach holds potential for reducing implant-centered infections and improving osseointegration.