title: Adsorption and release of BMP-2 on nanocrystalline apatite-coated and uncoated hydroxyapatite/beta-tricalcium phosphate porous ceramics.
abstract: The association of bone morphogenetic proteins (BMPs) with calcium phosphate bioceramics is known to confer them osteoinductive properties. The aim of this study was to evaluate the surface properties, especially regarding recombinant human BMP-2 (rhBMP-2) adsorption and release, of commercial sintered biphasic calcium phosphate ceramics after coating with biomimetic nanocrystalline apatite. The raw and coated ceramics exhibited similar macroporous structures but different nanometer-sized pores contents. Both types of ceramics showed Langmuir-type adsorption isotherms of rhBMP-2. The coating noticeably increased the rate of adsorption and the total amount of growth factor taken up, but the maximum coverage per surface area unit as well as the affinity constant appeared lower for coated ceramics compared with raw ceramic surfaces. The limited advantage gained by coating the ceramics can be assigned to a lower accessibility of the surface adsorption sites compared with the raw ceramics. The quantity of rhBMP-2 spontaneously released in cell culture medium during the first weeks was lower for coated samples than for uncoated ceramics and represented a minor fraction of the total adsorbed amount. In conclusion, the nanocrystalline apatite coating was found to favor the adsorption of rhBMP-2 while providing a mean to fine tune the release of the growth factor.
authors: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 31077 Toulouse Cedex 4, France.|Université de Toulouse, Biomechanics Laboratory EA3697, CHU Purpan, 31059 Toulouse Cedex, France.
authors: Hélène
authors: H
authors: Autefage
authors: INSERM U563, Centre de physiopathologie de Toulouse Purpan, Dept. Lipoprotéines et Médiateurs Lipidiques, CHU Purpan, 31024 Toulouse Cedex 3, France.
authors: Fabienne
authors: F
authors: Briand-Mésange
authors: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 31077 Toulouse Cedex 4, France.
authors: Sophie
authors: S
authors: Cazalbou
authors: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 31077 Toulouse Cedex 4, France.
authors: Christophe
authors: C
authors: Drouet
authors: INSERM U858, Institut Louis Bugnard, 31432 Toulouse Cedex 4, France.
authors: Daniel
authors: D
authors: Fourmy
authors: Teknimed, Z.I. de Montredon, 31240 L'Union, France.
authors: Stéphane
authors: S
authors: Gonçalvès
authors: INSERM U563, Centre de physiopathologie de Toulouse Purpan, Dept. Lipoprotéines et Médiateurs Lipidiques, CHU Purpan, 31024 Toulouse Cedex 3, France.
authors: Jean-Pierre
authors: JP
authors: Salles
authors: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 31077 Toulouse Cedex 4, France.
authors: Christèle
authors: C
authors: Combes
authors: Université de Toulouse, Biomechanics Laboratory EA3697, CHU Purpan, 31059 Toulouse Cedex, France.
authors: Pascal
authors: P
authors: Swider
authors: Université de Toulouse, CIRIMAT, UPS-INPT-CNRS, ENSIACET, 31077 Toulouse Cedex 4, France.
authors: Christian
authors: C
authors: Rey
mesh_terms: D000327:Adsorption; D000465:Algorithms; D001031:Apatites / Q000737:chemistry*; D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D016062:Porosity; D011208:Powders; D011994:Recombinant Proteins / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D011208:Powders; D011994:Recombinant Proteins; D017886:Durapatite; C018392:tricalcium phosphate