Polarization of Femtosecond Laser for Titanium Alloy Nanopatterning Influences Osteoblastic Differentiation

• Published in: Nanomaterials (Basel, Switzerland) Switzerland), 2022-05, Vol.12 (10), p.1619
• Main Authors: Maalouf, Mathieu, Abou Khalil, Alain, Di Maio, Yoan, Papa, Steve, Sedao, Xxx, Dalix, Elisa, Peyroche, Sylvie, Guignandon, Alain, Dumas, Virginie
• Format: Article
• Language: English
• Subjects: Alkaline phosphatase; Anisotropy; Bioengineering; Biofilms; Biological effects; Biomaterials; Biomedical materials; cell adhesion; Cell adhesion & migration; Cell differentiation; Cellular Biology; Continuous radiation; Differentiation (biology); Engineering Sciences; Extracellular matrix; femtosecond laser processing; Femtosecond pulsed lasers; Fibronectin; human mesenchymal stem cell; Influence; Isotropy; Laser beams; Lasers; Life Sciences; Mesenchyme; Micro and nanotechnologies; Microelectronics; Microscopy; Mineralization; multiscale patterning; Nanopatterning; Osseointegration; Osteoblastogenesis; Osteogenesis; Pattern formation; Polarization; radial LIPSS; Stem cells; Subcellular Processes; Surface structure; Surgical implants; Texturing; Titanium; Titanium alloys; Titanium base alloys; Topography; Transplants & implants; Ultrafast lasers
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano12101619

Ultrashort pulse lasers have significant advantages over conventional continuous wave and long pulse lasers for the texturing of metallic surfaces, especially for nanoscale surface structure patterning. Furthermore, ultrafast laser beam polarization allows for the precise control of the spatial alignment of nanotextures imprinted on titanium-based implant surfaces. In this article, we report the biological effect of beam polarization on human mesenchymal stem cell differentiation. We created, on polished titanium-6aluminum-4vanadium (Ti-6Al-4V) plates, a laser-induced periodic surface structure (LIPSS) using linear or azimuthal polarization of infrared beams to generate linear or radial LIPSS, respectively. The main difference between the two surfaces was the microstructural anisotropy of the linear LIPSS and the isotropy of the radial LIPSS. At 7 d post seeding, cells on the radial LIPSS surface showed the highest extracellular fibronectin production. At 14 days, qRT-PCR showed on the same surface an increase in osteogenesis-related genes, such as alkaline phosphatase and osterix. At 21 d, mineralization clusters indicative of final osteoinduction were more abundant on the radial LIPSS. Taken together, we identified that creating more isotropic than linear surfaces enhances cell differentiation, resulting in an improved osseointegration. Thus, the fine tuning of ultrashort pulse lasers may be a promising new route for the functionalization of medical implants.