title: Biofunctionalization strategies on tantalum-based materials for osseointegrative applications.
abstract: The use of tantalum as biomaterial for orthopedic applications is gaining considerable attention in the clinical practice because it presents an excellent chemical stability, body fluid resistance, biocompatibility, and it is more osteoconductive than titanium or cobalt-chromium alloys. Nonetheless, metallic biomaterials are commonly bioinert and may not provide fast and long-lasting interactions with surrounding tissues. The use of short cell adhesive peptides derived from the extracellular matrix has shown to improve cell adhesion and accelerate the implant's biointegration in vivo. However, this strategy has been rarely applied to tantalum materials. In this work, we have studied two immobilization strategies (physical adsorption and covalent binding via silanization) to functionalize tantalum surfaces with a cell adhesive RGD peptide. Surfaces were used untreated or activated with either HNO3 or UV/ozone treatments. The process of biofunctionalization was characterized by means of physicochemical and biological methods. Physisorption of the RGD peptide on control and HNO3-treated tantalum surfaces significantly enhanced the attachment and spreading of osteoblast-like cells; however, no effect on cell adhesion was observed in ozone-treated samples. This effect was attributed to the inefficient binding of the peptide on these highly hydrophilic surfaces, as evidenced by contact angle measurements and X-ray photoelectron spectroscopy. In contrast, activation of tantalum with UV/ozone proved to be the most efficient method to support silanization and subsequent peptide attachment, displaying the highest values of cell adhesion. This study demonstrates that both physical adsorption and silanization are feasible methods to immobilize peptides onto tantalum-based materials, providing them with superior bioactivity.
authors: Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgical Engineering, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028, Barcelona, Spain, carles.mas.moruno@upc.edu.
authors: Carlos
authors: C
authors: Mas-Moruno
authors: Beatriz
authors: B
authors: Garrido
authors: Daniel
authors: D
authors: Rodriguez
authors: Elisa
authors: E
authors: Ruperez
authors: F Javier
authors: FJ
authors: Gil
mesh_terms: D000327:Adsorption; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000528:radiation effects; D006801:Humans; D008422:Materials Testing; D009842:Oligopeptides / Q000737:chemistry* / Q000187:drug effects / Q000528:radiation effects; D016348:Osseointegration / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology*; D010126:Ozone / Q000494:pharmacology; D011485:Protein Binding; D013499:Surface Properties / Q000187:drug effects / Q000528:radiation effects; D013635:Tantalum / Q000737:chemistry* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D020099:Coated Materials, Biocompatible; D009842:Oligopeptides; D013635:Tantalum; D010126:Ozone; C047981:arginyl-glycyl-aspartic acid