Prolonged antibiotic delivery from anodized nanotubular titanium using a co-precipitation drug loading method

Area of Science:

• Biomaterials Science
• Nanotechnology
• Orthopedic Surgery

Background:

• Titanium is a common orthopedic implant material.
• Nanotechnology enables novel biomaterial surface modifications for enhanced functionality.
• Current drug delivery methods from implants have limited release durations.

Purpose of the Study:

• To engineer nanotubular titanium surfaces for enhanced orthopedic applications.
• To develop a sustained local antibiotic delivery system from these nanotubular surfaces.
• To evaluate the impact of drug-loaded coatings on bone cell functions.

Main Methods:

• Anodization of titanium to create nanotubular surface structures (80 nm inner diameter, 200 nm deep).
• Loading of nanotubular titanium with penicillin-based antibiotics via co-precipitation with calcium phosphate in simulated body fluid.
• In vitro assessment of osteoblast (bone-forming cell) adhesion on drug-loaded and non-loaded surfaces.
• Analysis of drug release kinetics and duration.

Main Results:

• Anodized nanotubular titanium surfaces promoted bone cell adhesion and differentiation compared to unanodized titanium.
• Co-precipitated coatings on nanotubular titanium enabled sustained drug release for up to 3 weeks, significantly longer than previous methods.
• Drug release followed a diffusion process governed by first-order kinetics.
• Drug-loaded coatings did not impede osteoblast adhesion, showing similar results to non-drug loaded coatings.

Conclusions:

• Nanotubular titanium surfaces offer a promising platform for sustained local drug delivery in orthopedic applications.
• The co-precipitation method provides a superior approach for loading antibiotics onto orthopedic implants.
• This surface treatment enhances implant biocompatibility and drug delivery capabilities, warranting further investigation.