title: Biological and physico-chemical assessment of hydroxyapatite (HA) with different porosity.
abstract: HA with specific internal porosities was loaded with different antibiotics (ATBs) and then tested on its microbiological effectiveness. The HA purity was controlled with X-ray diffraction, IR and Raman spectrometry. Varying the sintering temperature and/or adding graphite and PMMA as porogenous agents lead to obtained micro- and meso-porosities. The biological tests concerned cell viability, proliferation and morphology (SEM), and the cytochemical staining of actin and vinculin. The micro- and meso-porous HA samples had an internal pore size of 1-10 microm and 10-50 microm, respectively. X-ray diffraction and FTIR confirmed the high purity of the HA. The cell viability tests with L132 cells confirmed the excellent cytocompatibility of HA, the graphite powder and the ATB vancomycine. Proliferation rate was assessed with MC3T3-E1 osteoblasts. All HA samples produced a higher proliferation than the controls; the micro-porous HA inducing the highest cell growth. The ATB impregnated HA also stimulated cell proliferation but in lower extend. Cytochemical staining of osteoblasts revealed a well-developed cytoskeleton with strong stress fibres. Labelling of the focal adhesion contacts with anti-vinculin showed a less developed adhesion process in the cells on the different HA substrates. It was possible to realize a highly pure hydroxyapatite with different but controlled porosities by varying the sintering temperature and/or addition of a porogenous agents. This purity and the micro-porosity stimulate significantly cell growth.
authors: Laboratoire des Matériaux et Procédés, EA 2443, UVHC, 59600 Maubeuge, France. jean-christophe.hornez@univ-valenciennes.fr
authors: J-C
authors: JC
authors: Hornez
authors: F
authors: F
authors: Chai
authors: F
authors: F
authors: Monchau
authors: N
authors: N
authors: Blanchemain
authors: M
authors: M
authors: Descamps
authors: H F
authors: HF
authors: Hildebrand
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D002130:Calcium Phosphates / Q000737:chemistry; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D017886:Durapatite / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D008422:Materials Testing; D051379:Mice; D010006:Osteoblasts / Q000187:drug effects / Q000502:physiology; D010316:Particle Size; D016062:Porosity; D033362:Powder Diffraction; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D017886:Durapatite; C020243:calcium phosphate