[Back]

F. Meirer, B. Pemmer, G. Pepponi, N. Zoeger, P. Wobrauschek, S. Sprio, A. Tampieri, J. Göttlicher, R. Steininger, S. Mangold, Paul Roschger, A. Berzlanovich, J. Hofstätter, C. Streli:
"Assessment of chemical species of lead accumulated in tidemarks of human articular cartilage by X-ray absorption near-edge structure analysis";
Journal of Synchrotron Radiation, 18 (2011), 238 - 244.

A highly specific accumulation of the toxic element lead was recently measured
in the transition zone between non-calcified and calcified normal human
articular cartilage. This transition zone, the so-called `tidemark´, is considered to
be an active calcification front of great clinical importance. However, little is
known about the mechanisms of accumulation and the chemical form of Pb in
calcified cartilage and bone. Using spatially resolved X-ray absorption near-edge
structure analysis (m-XANES) at the Pb L3-edge, the chemical state of Pb in the
osteochondral region was investigated. The feasibility of the m-XANES set-up
at the SUL-X beamline (ANKA synchrotron light source) was tested and
confirmed by comparing XANES spectra of bulk Pb-reference compounds
recorded at both the XAS and the SUL-X beamline at ANKA. The m-XANES
set-up was then used to investigate the tidemark region of human bone (two
patella samples and one femoral head sample). The spectra recorded at the
tidemark and at the trabecular bone were found to be highly correlated with the
spectra of synthetic Pb-doped carbonated hydroxyapatite, suggesting that in
both of these very different tissues Pb is incorporated into the hydroxyapatite
structure.

X-ray absorption spectroscopy; Pb L3-edge XANES; human bone; tidemark; trabecular bone

http://dx.doi.org/10.1107/SO909049510052040

http://publik.tuwien.ac.at/files/PubDat_195697.pdf