Raman Microspectrometry Studies of Calcified Tissues and Related Biomaterials. Raman Studies of Calcium Phosphate Biomaterials Badania mikrospektrometryczne tkanek zmineralizowanych i związanych z nimi biomateriałów

Background. Raman spectroscopy, mainly focused on the vibration modes of PO4 , OH – , HPO4 2– and CO3 , has been provided to complementary information about calcium phosphate of biological interest. Objectives. In this study the composition of biological calcium phosphates was investigated by micro−Raman spec− trometry and compared to synthetic compounds. Material and Methods. Micro−Raman spectroscopy has been performed on synthetic apatitic compounds: hydro− xyapatite, β tricalciumphosphate, and type A and B carbonated apatites (OHAp, β−TCP and A and BCarAp, respec− tively). The assays on biological tissues were performed on human second premolars and rabbit bone. The spec− trum analysis are mainly focused on the vibration modes of PO4 3– , OH – , HPO4 and CO3 . Results. The OHAp spectrum is dominated by the OH – mode and the 4 internal modes of phosphate. The strong and narrow band of the ν1 mode at 964 cm –1 is specific of the stoechiometric OHAp. On β−TCP, completely OH deficient, the ν1 mode splits on two bands. With the carbonate substitution, we observed a frequency shift of this band. Additionally, the A type and B type carbonate substitutions are separately identified by two bands at 1107 and 1070 cm –1 respectively. The biominerals exhibit a AB type CarAp structure. Dentine and bone are very simi− lar and seem OH – deficient whereas enamel exhibits two bands in the OH – stretching mode region. Applications of the Raman technique for quantitative determination is also exposed with the help of a brushite cement. Conclusions. Further studies are now developed to obtain new information from an intravital bone chamber im− planted in rabbit model (Dent. Med. Probl. 2003, 40, 1, 37–43).