Journal of Dental Research, Vol 75, 1865-1870, Copyright © 1996 by International & American Associations for Dental Research Online Journals
Surface spectroscopy of apatitic materials: limitations and concerns
D. M. Wieliczka, P. Spencer and R. Z. LeGeros
Department of Physics, University of Missouri-Kansas City 64110, USA.
The use of x-ray photoelectron spectroscopy for the study of biological
materials has provided mixed results. The experimental difficulties
associated with the application of this technique to the study of
biological materials include the effects of ultra-high vacuum, x-ray
exposure, surface charging, and, for insulating materials, the inherent
lack of an intrinsic energy reference. Since most biological materials are
insulators, the lack of an intrinsic energy reference complicates one's
ability to draw direct comparisons between different studies. In this
paper, the results from two different apatites are compared with the
results obtained from the use of two conventional techniques for
referencing binding energies. The results presented here are referenced
only to the Pt Fermi level; no further energy modifications are performed.
A comparison with the results of other investigators indicates a large
difference in binding energies for all involved core levels. These results
indicate that, in the study of insulating materials with x-ray
photoelectron spectroscopy, it is essential that all data be acquired under
exacting conditions on the same experimental system.
