Plasma-Activated Tropoelastin Functionalization of Zirconium for Improved Bone Cell Response

0466481 - FGÚ 2017 RIV US eng J - Článek v odborném periodiku
Yeo, G. C. - Santos, M. - Kondyurin, A. - Lišková, Jana - Weiss, A. S. - Bilek, M. M. M.
Plasma-Activated Tropoelastin Functionalization of Zirconium for Improved Bone Cell Response.
ACS BIOMATERIALS SCIENCE & ENGINEERING. Roč. 2, č. 4 (2016), s. 662-676. ISSN 2373-9878. E-ISSN 2373-9878
Grant CEP: GA MZd(CZ) NV15-32497A; GA MŠMT(CZ) ED1.1.00/02.0109
Institucionální podpora: RVO:67985823
Klíčová slova: bone * plasma-activated coating * titanium * tropoelastin * zirconium
Kód oboru RIV: EI - Biotechnologie a bionika
Impakt faktor: 3.234, rok: 2016

The mechanical strength, durability, corrosion resistance, and biocompatibility of metal alloys based on zirconium (Zr) and titanium (Ti) make them desirable materials for orthopedic implants. However, as bioinert metals, they do not actively promote bone formation and integration. Here we report a plasma coating process for improving integration of such metal implants with local bone tissue. The coating is a stable carbon based plasma polymer layer that increased surface wettability by 28%, improved surface elasticity to the range exhibited by natural bone, and additionally covalently bound the extracellular matrix protein, tropoelastin, in an active conformation. The thus biofunctionalized material was significantly more resistant to medical-grade sterilization by steam, autoclaving or gamma-ray irradiation, retaining >60% of the adhered tropoelastin molecules and preserving full bioactivity. The interface of the coating and metal was robust so to resist delamination during surgical insertion and in vivo deployment, and the plasma process employed was utilized to also coat the complex 3D geometries typical of orthopedic implants. Osteoblast-like osteosarcoma cells cultured on the biofunctionalized Zr surface exhibited a significant 30% increase in adhesion and up to 70% improvement in proliferation. Cells on these materials also showed significant early stage up-regulation of bone marker expression (alkaline phosphatase, 1.8 fold; osteocalcin, 1.4 fold), and sustained up-regulation of these genes (alkaline phosphatase, 1.3 fold; osteocalcin, 1.2 fold) in osteogenic conditions. In addition, alkaline phosphatase production significantly increased (2-fold) on the functionalized surfaces, whereas bone mineral deposition increased by 30% above background levels compared to bare Zr. These findings have the potential to be readily translated to the development of improved Zr and Ti-based implants for accelerated bone repair.
Trvalý link: http://hdl.handle.net/11104/0264761