Preparation of porous scaffolds of borosilicate bioglass

Abstract

A borosilicate bioglass in Na 2O-CaO-SiO 2-P 2O 5- B 2O 3 system is a bioactive and biodegradable material for tissue engineering. In this study, the bioactive porous scaffolds with three-dimensional interconnection were fabricated by replication technique, using borosilicate bioglass powder to form slurry with ethanol as solvent and ethyl-cellulose as additive. The compressive strength of scaffolds increases from 0.03MPa to 0.36MPa by adjusting the slurry load, the solid concentration and the ethyl-cellulose concentration in the slurry, while the pore size of scaffolds remains in the rangeot 300-500μm and the porosity maintains over 80%. According the analysis on Cellular Structure Model, it is suggested that employing high strength glass and optimizing slurry composition are effective approaches to improve cellular structure and increase scaffold strength. The compressive strength of another borosilicate glass scaffolds made from Na 2O-K 2O-MgO-CaO-SiO 2- P 2O 5-B 2O 3 system can reach 5-8MPa based on the theory. These experiments show that the replication technique is a promising way to prepare bioglass scaffolds.

Na2O-CaO-SiO2-P2O5-B2O3系硼硅酸鹽生物玻璃是一類具有良好生物活性和降解性能的組織工程材料.本研究中,采用有機泡沫浸漬法,乙醇作溶劑,乙基纖維素作添加劑,將硼硅酸鹽玻璃粉體制備成具有三維連通網狀結構的組織工程多孔支架.通過調節漿料的固相含量和乙基纖維素含量,改善坯體的涂覆量,在支架孔徑為300～500μm,孔隙率高于80%時,使支架抗壓強度從0.03MPa提高到0.36MPa.根據蜂窩狀結構模型分析,發現采用高強度玻璃,優化漿料是改善多孔材料結構和力學性能的有效途徑.用該模型理論指導,由Na2O-K2O-MgO-CaO·SiO2-P2O5-B2O3系統制成的另一種硼硅酸鹽玻璃支架,其抗壓強度可達5～8MPa.實驗表明有機泡沫浸漬法在制備組織工程支架中有廣泛的應用前景.