The crystallographic properties of hydroxyapatites synthesized at temperatures of 200 degrees C, 500 degrees C, 900 degrees C and 1250 degrees C, designated HAP200, HAP500, HAP900 and HAP1250, respectively, were studied using X-ray powder diffraction. Values of a-axis length for the hydroxyapatites ranged from 9.406 A to 9.416 A, which were smaller than the corresponding value for stoichimetric...

Effect of SiO2 addition on the microstructures of calcium-deficient hydroxyapatite prepared by the heat-treatments was examined. Obtained hydroxyapatites substituted with Si ion were characterized by XRD, FT-IR and XAFS measurements. XANES results of Si K-edge and P K-edge in these modified hydroxyapatites indicated the shift of peaks of P K-edge with the SiO2 contents, although no change of Si...

The efforts in this study were initiated to develop and validate new solid phases for estimation of hormones by radioimmunoassay (RIA). The study argued the successful application of different hydroxyapatites (HAP) as new solid phases for estimation of Alpha fetoprotein (AFP), Thyroid Stimulating hormone (TSH) and Luteinizing hormone (LH) in human serum. Hydroxyapatites have different alkali ea...

A series of nanocrystalline calcium hydroxyapatites was prepared by dry milling and characterized using proton and 31P MAS NMR, TEM, and TGA methods. The samples contained stubby rod-shaped crystals, which length and width varied in the 130-30 and 95-20 nm ranges, respectively. It was confirmed that concentration of structural hydroxyl groups in nanocrystalline apatites decreases with the decre...

Thermodynamics of the precipitation calcium phosphates shows importance pH and order introduction precursor ions on textural (morphology, surface area) structural (defects) properties hydroxyapatites.

Reconstructive surgery is presently struggling with the problem of infections located within implantation biomaterials. Of course, the best antibacterial protection is antibiotic therapy. However, oral antibiotic therapy is sometimes ineffective, while administering an antibiotic at the location of infection is often associated with an unfavourable ratio of dosage efficiency and toxic effect. T...