Interaction Between Titanium Implant Surfaces and Hydrogen Peroxide in Biologically Relevant Environments
- PDF / 171,589 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 6 Downloads / 182 Views
W11.17.1
Interaction Between Titanium Implant Surfaces and Hydrogen Peroxide in Biologically Relevant Environments Julie Muyco1,2, Timothy Ratto1, Christine Orme1, Joanna McKittrick2, John Frangos3 1 Chemistry and Materials Science, Lawrence Livermore National Laboratory, Livermore, CA 94550, U.S.A. 2 Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, U.S.A. 3 La Jolla Bioengineering Institute, La Jolla, CA 92037, U.S.A. ABSTRACT Titanium was exposed to dilute solutions of hydrogen peroxide (H2O2) to better characterize the interaction at the interface between the solution and metal. The intensity of light passing through films of known thickness of titanium on quartz was measured as a function of time in contact with H2O2 in concentrations of 0.3% and 1.0%. An atomic force microscope (AFM) was used to record deflection-distance (force) curves as a probe approached the interface of titanium in contact with solution containing 0.3% of H2O2 . The interaction layer measured using AFM techniques was much greater than the thickness of the titanium films used in this study. Raman spectroscopy taken during interaction shows the emergence of a Ti-peroxy gel and titania after 2 hours in contact with 0.3% H2O2 solution. INTRODUCTION Titanium has been widely used as an implant material due to its corrosion resistance and ability to osseointegrate, or to allow bone tissue to grow flush against the implant. These characteristics of titanium implants can be attributed to the oxide layer found on the surface. These studies aim to further the understanding of the role of the interaction between titanium implant surfaces and hydrogen peroxide in the ability of titanium implants to be accepted in the body. Hydrogen peroxide is produced in higher concentration during wound healing. Titanium interacts with hydrogen peroxide to make a Ti-peroxy gel (TiOOH): [1] 2TiO2 + H2O2 + 2e- → Ti2O3 +H2O + O2
(1)
Ti2O3 + H2O2 → 2TiO2 + H2O +2e-
(2)
TiO2(H2O) + H+ + e- → TiOOH(H2O)n
(3)
The gel may serve many purposes that this study hopes to define. Among these are the ability to mediate reactive species produced during the wound healing process [2], influence the adhesion of proteins or the nucleation of bone mineral [3], and to serve as an intermediate layer that transitions mechanical properties between the stiff titanium and surrounding tissue. Using AFM force curves, Raman spectroscopy and by observing changes in the optical properties of the material as a function of time exposed to hydrogen peroxide solution, the kinetics of the development of the Ti-peroxy gel as well as the mechanical properties of the gel can be determined.
W11.17.2
EXPERIMENTAL METHODS Thin films of titanium were deposited on to quartz microscope slides obtained from G.M. Associates, Inc. (Oakland, California) using E-beam evaporation. Deposition thickness was monitored with a quartz crystal microbalance and varied from 10 nm to 50 nm. Solutions of hydrogen peroxide were made from 30% (8.8M) stock solution (VWR,
Data Loading...
