Vol.3 No.3 (May 2013)
Release Performance in Vitro of nHA/PLGA Scaffolds Contained with Protein Sustained-Release PLLA Microspheres Prepared by Means of Supercritical Fluid Foaming Technology
In order to construct a bone regeneration system that different cell factors controlled release at proper stage, Trypsin (Try) was selected as the model protein, and the composite of sustained-release microspheres and biodegradable porous scaffolds was prepared in this study. First of all, Try loaded poly-l-lactic acid microspheres (Try-PLLAms) were prepared, and then compounded to the nano hydroxyapatite/poly lactic-co-glycolic acid (nHA/PLGA) to build a scaffold that can release growth factors sequentially. The results showed that the Try-PLLAms were spherical shape with diameters of 2 - 7 μm. The encapsulation efficiency of the Try in PLLAms was 80.5%, and the loading capacity was 0.89%. The prepared Try-PLLAms/nHA/PLGA scaffold possessed 150 - 300 μm pore diameter, 50.9% - 76.8% porosity, 3.9 - 5.1 MPa compressive strength, and 19.8% degradation at 8 weeks. The cumulative releases of Try from Try- nHA/PLGA scaffolds and from Try-PLLAms were respectively about 85% and 65.2% at 48 hours, and that from Try-PLLAms/nHA/ PLGA scaffolds were 32.9% at 48 hours and 60.6% at 21 days. The results demonstrated that Try-PLLAms/nHA/PLGA scaffolds had excellent drug release performance with suitable compressive strength, which would be used as tissue engineering scaffolds with protein delivery.
李培培 , 白燕 , 尹光福 (2013) 超临界流体发泡技术制备含PLLA缓释微球nHA/PLGA复合支架及体外释放性能研究。 材料科学， 3， 110-115. doi: 10.12677/MS.2013.33021
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