Hydroxyapatite is the mineral component of human bones and teeth enamel and is used as synthetic biomaterial. It also grows outside bioglasses as a response of their incorporation in body fluids. The focus is then on understanding the microscopic steps occurring at its surfaces as this allows researchers to understand the key features of biomolecular adhesion. This perspective article deals with in silico simulations of these processes by quantum-mechanical methods based on density functional theory using the hybrid B3LYP functional and Gaussian basis functions.
"In one case Al 3+ deposits were observed in the calcified cartilage. From a crystallographic point of view, Al or Fe can substitute a Ca atom in the large channel of the hydroxyapatite crystal in position (6 h)  . In this channel centered by a hydroxide group, the six calcium atoms are surrounded by the phosphate groups and when Al is adsorbed, it is linked to the PO 4 3− groups . "
[Show abstract][Hide abstract] ABSTRACT: We present the ab initio molecular dynamics code CPMD. This plane wave/pseudopotential based Kohn-Sham density functional code with a rich set of features is successfully applied to calculate static and dynamic properties for a wide range of molecules and materials. Its flexibility and high performance on many computer platforms make it an optimal tool for the study of liquids, surfaces, crystals as well as biomolecules.
Zeitschrift für Kristallographie 01/2005; 220(5-6). DOI:10.1524/zkri.220.5.549.65080 · 1.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This paper is an extension of previous work devoted to the characterization of platelet-like hydroxyapatite (HA) nanoparticles constituted by a crystalline core coated by an amorphous surface layer 1−2 nm thick (Bertinetti et al. J. Phys. Chem. C. 2007, 111, 4027−4035). By increasing the preparation temperature, the platelet morphology was retained but HA nanoparticles exhibited a higher degree of crystallinity (evaluated by X-ray diffractometry). High-resolution transmission electron microscopy revealed that, in this case, the crystalline order was extended up to the particles’ surfaces, which were of the (010), (100), and (001) types. IR spectroscopy was used to investigate the surface hydration of both materials, in terms of adsorbed H2O molecules and surface hydroxy groups, as well as the Lewis acidity of surface cations, by removing water and adsorbing CO. For both features, strong similarities between amorphous and crystalline surfaces were found.
The Journal of Physical Chemistry C 09/2010; 114(39). DOI:10.1021/jp105971s · 4.77 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.