title: In vitro evaluation of human osteoblast adhesion to a thermally oxidized gamma-TiAl intermetallic alloy of composition Ti-48Al-2Cr-2Nb (at.%).
abstract: Ti-48Al-2Cr-2Nb (at.%) (gamma-TiAl), a gamma titanium aluminide alloy originally designed for aerospace applications, appears to have excellent potential as implant material. Thermal treatment of gamma-TiAl renders this alloy extremely corrosion resistant in vitro, which could improve its biocompatibility. In this study, the surface oxides produced by thermal oxidation (at 500 degrees C, and at 800 degrees C for 1 h in air) on gamma-TiAl were characterized by X-ray photoelectron spectroscopy (XPS). hFOB 1.19 cell adhesion on thermally oxidized gamma-TiAl was examined in vitro by a hexosaminidase assay, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) after 1, 7 and 14 days. Ti-6Al-4V surfaces were used for comparison. Hexosaminidase assay data and CLSM analysis of focal contacts and cytoskeleton organization showed no differences in cell attachment on autoclaved and both heat-treated gamma-TiAl surfaces at the different time points. SEM images showed well organized multi-layers of differentiated cells adhered on thermally oxidized gamma-TiAl surfaces at day 14. Unexpectedly, thermally oxidized Ti-6Al-4V surfaces oxidized at 800 degrees C exhibited cytotoxic effects on hFOB 1.19 cells. Our results indicate that thermal oxidation of gamma-TiAl seems to be a promising method to generate highly corrosion resistant and biocompatible surfaces for implant applications.
authors.affiliation: Department of Biology, University of Puerto Rico, Call Box 9000, Mayagüez Campus, Mayagüez, PR 00681-9000, USA.
authors.forename: Samir A
authors.initials: SA
authors.lastname: Bello
authors.forename: Idaris
authors.initials: I
authors.lastname: de Jesús-Maldonado
authors.forename: Esteban
authors.initials: E
authors.lastname: Rosim-Fachini
authors.forename: Paul A
authors.initials: PA
authors.lastname: Sundaram
authors.forename: Nanette
authors.initials: N
authors.lastname: Diffoot-Carlo
mesh_terms: D000497:Alloys / Q000737:chemistry* / Q000378:metabolism; D002448:Cell Adhesion; D003343:Corrosion; D003764:Dental Materials / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010006:Osteoblasts / Q000166:cytology*; D010084:Oxidation-Reduction; D056951:Photoelectron Spectroscopy; D055585:Physical Phenomena; D019736:Prostheses and Implants; D000267:Tissue Adhesions; D014025:Titanium / Q000737:chemistry* / Q000378:metabolism; D014965:X-Rays
chemical_list: D000497:Alloys; D003764:Dental Materials; D014025:Titanium