Surface Modification of Polyetheretherketone (PEEK) via Femtosecond Laser Microprocessing for Enhanced Bioactivity: A Preliminary Study

The increasing prevalence of orthopedic disorders and technological advances have significantly improved the design and functionality of orthopedic implants, fostering the growth of the orthopedic implant market. Polyetheretherketone (PEEK) has emerged as a promising alternative to the gold standard of metallic implants due to its favorable biocompatibility and mechanical properties, comparable to those of bone tissue. However, its chemical inertness results in poor osseointegration. This study investigates femtosecond (fs) laser-induced micro- and nanoscale surface modifications of PEEK, aiming to develop surface modifications potentially favorable for bioactivity enhancement of the as-created transient cellular scaffolds. Various texturing designs were fabricated by precisely controlling the laser parameters applied (laser beam power P = 20-80 mW, hatch spacing dx = 45-100 µm, scanning velocity V = 3.44-32 mm/s). The resulting morphologies were characterized by SEM, EDX, XRD, micro-Raman, 3D profilometry, water contact angle measurements, and evaluated for preliminary biological response. The main achievement of the research indicates that the hierarchical topography created by fs laser microprocessing significantly increased surface morphology, which may subsequently provide surface conditions supporting successful osseointegration. These findings demonstrate the feasibility of femtosecond laser structuring as a promising, reproducible, and environmentally friendly method for sustainable surface biofunctionalization of PEEK in orthopedic applications.