Assessment of chemical species of lead accumulated in tidemarks of human articular cartilage by X-ray absorption near-edge structure analysis

作者：Meirer Florian; Pemmer Bernhard^*; Pepponi Giancarlo; Zoeger Norbert; Wobrauschek Peter; Sprio Simone; Tampieri Anna; Goettlicher Joerg; Steininger Ralph; Mangold Stefan; Roschger Paul; Berzlanovich Andrea; Hofstaetter Jochen G; Streli Christina

来源：JOURNAL OF SYNCHROTRON RADIATION, 2011, 18(2): 238-244.

DOI：10.1107/S0909049510052040

• X-ray absorption spectroscopy
• Pb L (3)-edge XANES
• human bone
• tidemark
• trabecular bone

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 (mu-XANES) at the Pb L (3)-edge, the chemical state of Pb in the osteochondral region was investigated. The feasibility of the mu-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 mu-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.

• 出版日期2011-3