Investigation of different bone matrices by vibrational spectroscopy

To study bones of various origins (human bone and bones from different animal species) the complementary spectral methods, infrared and Raman spectroscopy, were used. The main vibrational bands characteristic to major constituents of bones, that is collagen and calcium phosphate, were identified. Mature deer antler has the same constituents. The relative content of the organics in different bones was evaluated from Raman spectra as an integration ratio between the v(CH) bands at 2825-3080 cm(-1) and the V-1[PO4](3-) band centered at 960 cm(-1). This ratio decreases in the order: mature deer antler > human skull > fish > pig. The thermal behaviour of bones was investigated by infrared spectroscopy. Heating of powdered bones produces at 200 degrees C the diminishing of the organic component, marked by the reduced intensity of the amide III band observed at 1239 cm(-1). The spectra of samples heated at 900 degrees C put in evidence the removal of organic components and the presence of a variety of hydroxyapatite with an improved cristallinity degree, especially in the case of fish bone.