We report the synthesis of nanoapatite crystals via a hydrothermal reaction of hydroxyapatite precipitates. The impact of the reaction conditions on the properties of the crystals obtained were evaluated. The hydrothermal reaction that takes place markedly affected the crystallinity, morphology, and size of the nanoapatite crystals formed. High crystallinity and large crystal size were obtained...

The remarkable properties of bone derive from a highly organized arrangement of coaligned nanometer-scale apatite platelets within a fibrillar collagen matrix. The origin of this arrangement is poorly understood and the crystal structures of hydroxyapatite (HAP) and the nonmineralized collagen fibrils alone do not provide an explanation. Moreover, little is known about collagen-apatite interact...

Calcium phosphate is deposited in many diseases, but formation mechanisms remain speculative. Nanobacteria are the smallest cell-walled bacteria, only recently discovered in human and cow blood and commercial cell culture serum. In this study, we identified with energy-dispersive x-ray microanalysis and chemical analysis that all growth phases of nanobacteria produce biogenic apatite on their c...

Major and minor elements of successively collected 70 Middle Triassic radiolarian bedded cherts from the Mino Belt in central Japan were studied. In order to reveal pre-diagenetic, primary geochemical signatures related to marine biogeochemical cycles, composite data of chert-shale couplets in addition to raw data were examined. The results show that Mn, Cu, Sr, Ba and P were supplied significa...

Apatite ore from Lao Cai province (Vietnam) has large reserves and low cost which was purified by a simple chemical method. one were characterized the molecular structure, phase component, specific surface area, element morphology IR, XRD, BET, EDX, SEM methods. The IR result shows both materials have functional groups of fluorapatite such as PO43- F-. XDR EDX confirm that main component is flu...

Physical and chemical characteristics of the water column and sediments at sea bass/sea bream farm located on the middle Adriatic island of Brač were investigated during the 2001-2006 period. Measurements and samplings were performed at stations inside the farm area and at reference station, approximately 1 km distant from the farm. Investigated parameters in the water column were temperature, ...

Objective To prepare nanocomposite cements based on the incorporation of bioactive glass nanoparticles (nBGs) into BiodentineTM (BD, Septodent, Saint-Maur-des-Fosses Cedex, France) and to assess their bioactive properties. Material and Methods nBGs were synthesised by the sol-gel method. BD nanocomposites (nBG/BD) were prepared with 1 and 2% nBGs by weight; unmodified BD and GC Fuji IX (GIC, ...

Zirconium oxide thin films were fabricated on silicon wafers using a filtered cathodic arc system in concert with oxygen plasma. The structure and phase composition of the zirconium oxide thin films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), and transmission electron microscopy (TEM). The bioactivity was assessed b...

Bone is a composite material in which collagen fibrils form a scaffold for a highly organized arrangement of uniaxially oriented apatite crystals. In the periodic 67 nm cross-striated pattern of the collagen fibril, the less dense 40-nm-long gap zone has been implicated as the place where apatite crystals nucleate from an amorphous phase, and subsequently grow. This process is believed to be di...

The aim of this work was to verify the existence of correlation between Raman spectroscopy readings of phosphate apatite (~960 cm-1), fluoridated apatite (~575 cm-1) and organic matrix (~1450 cm-1) levels and Diagnodent® readings at different stages of dental caries in extracted human teeth. The mean peak value of fluorescence in the carious area was recorded and teeth were divided in enamel ca...