Quantum mechanical simulation of bio-glasses
and their interface
Prof. P. Ugliengo
Dipartimento di Chimica I.F.M, NIS Centre of Excellence and INSTM National Consortium, Università degli Studi di Torino,
via P. Giuria 7- 10125 Torino, Italie
Vendredi 3 juillet 2009, 11h00
The Hench Bioglass® 45S5 of 46.1% SiO2, 26.9% CaO, 24.4% Na2O and 2.6% P2O5
molar composition is of great interest in medical applications since in the
presence of body fluids, and depending upon the rate of ion release and
resorption, it creates chemical gradients which promote the formation of a
layer of biologically active bone-like hydroxyapatite at the implantation
interface. Osteoblasts can preferentially proliferate on the apatite layer,
and differentiate to form new bone that binds strongly to the implant surface.
Hydroxyapatite [HA, Ca10(PO4)6(OH)2] is the main constituent of the mineral
phase in mammalian bones and teeth enamel. For this reason, HA is widely
applied as an orthopaedic and dental biomaterial, both per se and together
with other classes of materials, in the form of coating for metal alloys, in
composites with polymers and so on.
In this seminar the quantum mechanical simulations carriedout at B3LYP
(within periodic boundary conditions asencoded in the CRYSTAL06 code) of both
Hench bioglass and HA is reported. For bioglass, structure, electronic and
vibrational features of the bulk are reported. For HA, bulk and main surfaces
either free and when interacting with H2O and glycine aminoacid will be
addressed.