version française rss feed
HAL : hal-00018605, version 1

Fiche détaillée  Récupérer au format
Colloids and Surfaces B42 (2005) 205
STEM and EDXS characterisation of physico-chemical reactions at the periphery of sol-gel derived Zn-substituted hydroxyapatites during interactions with biological fluids
Jean-Marie Nedelec1, Edouard Jallot2, Anne Sophie Grimault2, Emmanuelle Chassot2, Alexia Grandjean Laquerriere3, Patrice Laquerriere3, Dominique Laurent Maquin3

With its good properties of biocompatibility and bioactivity hydroxyapatite (HA) is highly used as bone substitutes and as coatings on metallic prostheses. In order to improve bioactive properties of HA we have elaborated Zn2+ doped hydroxyapatite. Zn2+ ions substitute for Ca2+ cations in the HA structure and four Zn concentrations (Zn/Zn+Ca) were prepared 0.5, 1, 2, 5 % at. To study physico-chemical reactions at the materials periphery, we immersed the bioceramics into biological fluids for delays from 1 day to 20 days. The surface changes were studied at the nanometer scale by scanning transmission electron microscopy associated to energy dispersive X-ray spectroscopy. After 20 days of immersion we observed the formation of a calcium-phosphate layer at the periphery of the HA doped with 5% of zinc. This layer contains magnesium and its thickness was around 200 nm. Formation of this Ca-P-Mg layer represents bioactivity properties of the 5% Zn-substituted hydroxyapatite. This biologically active layer improves properties of HA and will permit a chemical bond between the ceramic and bone.
1 :  LMI - Laboratoire des Matériaux Inorganiques
2 :  LPC - Laboratoire de Physique Corpusculaire [Clermont-Ferrand]
3 :  Interfaces biomatériaux/tissus hôtes
hydroxyapatite – zinc – bioactivity – electron probe microanalysis – sol-gel
Liste des fichiers attachés à ce document : 
HAPZN-Jallot-revised.pdf(716.3 KB)