A new sol-gel synthesis of 45S5 bioactive glass using an organic acid as catalyst.

Fiche publication


Date publication

février 2015

Journal

Materials science & engineering. C, Materials for biological applications

Auteurs

Membres identifiés du Cancéropôle Est :
Dr EL BTAOURI Hassan


Tous les auteurs :
Faure J, Drevet R, Lemelle A, Ben Jaber N, Tara A, El Btaouri H, Benhayoune H

Résumé

In this paper a new sol-gel approach was explored for the synthesis of the 45S5 bioactive glass. We demonstrate that citric acid can be used instead of the usual nitric acid to catalyze the sol-gel reactions. The substitution of nitric acid by citric acid allows to reduce strongly the concentration of the acid solution necessary to catalyze the hydrolysis of silicon and phosphorus alkoxides. Two sol-gel powders with chemical compositions very close to that of the 45S5 were obtained by using either a 2M nitric acid solution or either a 5mM citric acid solution. These powders were characterized and compared to the commercial Bioglass®. The surface properties of the two bioglass powders were assessed by scanning electron microscopy (SEM) and by Brunauer-Emmett-Teller method (BET). The Fourier transformed infrared spectroscopy (FTIR) and the X-ray diffraction (XRD) revealed a partial crystallization associated to the formation of crystalline phases on the two sol-gel powders. The in vitro bioactivity was then studied at the key times during the first hours of immersion into acellular Simulated Body Fluid (SBF). After 4h immersion into SBF we clearly demonstrate that the bioactivity level of the two sol-gel powders is similar and much higher than that of the commercial Bioglass®. This bioactivity improvement is associated to the increase of the porosity and the specific surface area of the powders synthesized by the sol-gel process. Moreover, the nitric acid is efficiently substituted by the citric acid to catalyze the sol-gel reactions without alteration of the bioactivity of the 45S5 bioactive glass.

Mots clés

45S5, Bioactive glass, Bioactivity, Citric acid, In vitro tests, Sol–gel

Référence

Mater Sci Eng C Mater Biol Appl. 2015 Feb;47:407-12