RÉSUMÉ
BACKGROUND:To date,no single material can completely meet the clinical requirements.However,the composite materials characterized by good biodegradability,biocompatibility and osteoconductivity have become a highlight of the artificial bone materials.OBJECTIVE:To synthesize the basic fibroblast growth factor (bFGF)-poly(lactic-co-glycolic acid) (PLGA) microspheres/hydroxyapatite (HA)/poly(I-lactic acid) (PLLA) porous bone scaffolds,and to observe the physicochemical properties and biocompatibility of the composite material.METHODS:The bFGF-PLGA microspheres were prepared by double emulsion method,and then six kinds of materials were made including PLLA,PLLNHA,PLLAJPLGA,PLLNHNPLGA,PLLNHA/bFGF,and bFGF-PLGA microspheres/PLLA/HA.The characterization of the materials were observed by particle size analyzer,transmission electron microscopy,X-ray diffraction,Fourier transform infrared spectrometer,microcomputer differential thermal balance,and scanning electron microscope.Toxicity of these materials and proliferation of bone marrow mesechymal stem cells seeded onto these materials were analyzed and compared.RESULTS AND CONCLUSION:The average particle size of bFGF-PLGA microspheres was about 250 nm,the average drug-loading capacity was (26.03±0.17)％,and the entrapment percentage was (90.65±2.68)％.The prepared bFGF-PLGA microspheres were spherical and had good dispersibility.In addition,all the six kinds of materials had a porous structure with similar pore diameter,in which the microspheres and particles exhibited a rational distribution.The toxic level of bFGF-PLGA microspheres/PLLNHA,bFGF/HNPLLA and HAP/PLLA was graded as 1 (with a relative survival rate ≥ 80％),indicating no obvious toxicity or slight toxicity.All these six kinds of composite materials can promote the proliferation of bone marrow mesenchymal stem cells,and the bFGF-PLGA microspheres/PLLNHA shows the best effects on cell proliferation and has good biocompatibility.