PEEK surface modification by fast ambient-temperature sulfonation for bone implant applications

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Orthopedic Engineering

Background:

• Polyetheretherketone (PEEK) is a promising biomaterial for bone implants due to its mechanical properties matching human bone.
• PEEK's bio-inert and hydrophobic surface hinders osseointegration, limiting its clinical application.
• Traditional PEEK sulfonation methods require high temperatures and long reaction times, unsuitable for direct biomedical surface modification.

Purpose of the Study:

• To develop a simple, fast, and economical ambient-temperature surface treatment for PEEK.
• To enhance the hydrophilicity and osteoconductivity of PEEK for improved bone implant osseointegration.
• To systematically investigate the effects of short-duration ambient-temperature sulfonation on PEEK surface properties.

Main Methods:

• Investigated three ambient-temperature sulfonation treatments with varying reaction times (5-90 seconds).
• Evaluated hydrophilicity (water contact angle) and surface morphology of modified PEEK samples.
• Determined an optimal treatment protocol involving sequential sulfuric acid and sodium hydroxide immersion and rinsing steps.

Main Results:

• An optimal 30-second ambient-temperature sulfonation treatment was established.
• The optimized PEEK surface treatment significantly reduced the water contact angle from 78° to 37°.
• This rapid sulfonation method proved more effective than conventional plasma treatments for enhancing PEEK hydrophilicity.

Conclusions:

• A novel, rapid, ambient-temperature sulfonation process effectively enhances PEEK surface hydrophilicity.
• The developed surface modification technique offers a viable strategy for improving PEEK bone implant osseointegration.
• This economical and fast treatment presents a significant advancement for PEEK-based orthopedic applications.