RGD Peptide-Functionalized Polyether Ether Ketone Surface Improves Biocompatibility and Cell Response.

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Tissue Engineering

Background:

• Polyether ether ketone (PEEK) is a biocompatible polymer with excellent mechanical properties and chemical stability, widely used in maxillofacial and orthopedic implants.
• However, PEEK's inert surface limits its bioactivity and interaction with surrounding tissues, necessitating surface modifications for enhanced implant-tissue integration.
• Developing bioactive surfaces is crucial for improving the performance and longevity of PEEK-based medical devices.

Purpose of the Study:

• To develop a bioactive surface on Polyether ether ketone (PEEK) through a multi-step surface modification process.
• To investigate the effect of oxygen plasma treatment, polydopamine (PDA) coating, and RGD peptide functionalization on PEEK's surface properties and bioactivity.
• To evaluate the in vitro cellular response to the modified PEEK surfaces for potential biomedical applications.

Main Methods:

• PEEK surface activation using oxygen plasma treatment.
• Deposition of a polydopamine (PDA) coating followed by biofunctionalization with RGD peptides.
• Surface characterization using contact angle measurements, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD).
• Quantification of immobilized peptide using UV-vis spectroscopy and in vitro cell culture studies (NIH/3T3 fibroblasts) to assess cell viability, attachment, spreading, and proliferation.

Main Results:

• Oxygen plasma treatment increased PEEK surface reactivity and hydrophilicity.
• XPS confirmed the successful deposition of PDA coating and immobilization of RGD peptides.
• XRD analysis provided information on crystallinity and phase identification of the modified PEEK.
• In vitro studies demonstrated significantly enhanced fibroblast viability, attachment, spreading, and proliferation on the peptide-functionalized PEEK surfaces compared to unmodified PEEK.
• A progressive increase in cellular response was observed with each successive surface modification step.

Conclusions:

• The combined approach of oxygen plasma treatment, PDA coating, and RGD peptide functionalization effectively renders PEEK surfaces bioactive.
• The modified PEEK surfaces exhibit improved cell interaction, indicating enhanced potential for implant-tissue integration.
• This surface engineering strategy offers a promising route for developing advanced PEEK-based biomaterials for orthopedic and maxillofacial applications.