XANES analysis of dried and calcined bones

The structure of dried and calcined bones from chicken, bovine, deer, pig, sheep and chamois was examined using X-ray Absorption Near Edge Structure (XANES) spectroscopy. The oxygen K-edge absorption edge indicates that the surface of dried bone has a larger proportion of carbonate than the interior that is made up of phosphates. The phosphorus L and K edge clearly indicate that pyrophosphates, alpha-tricalcium phosphate (alpha-TCP) and hydrogen phosphates of Ca do not exist in either the dried bone or calcined bone and phosphorus exists as either beta-tricalcium phosphate (beta-TCP) or hydroxyapatite, both in the dried and calcined conditions. The Ca K-edge analysis indicates that beta-TCP is the likely form of phosphate in both the dried and calcined conditions. (C) 2013 Elsevier B.V. All rights reserved.