基于微球孔内团聚的多孔钛表面药物释放技术

通过含药物的微球在骨植入材料表面微孔内团聚方法解决现有骨植入材料表面药物释放技术缺乏通用性、无法控制释放速度的问题.用乳液法合成负载不同含量庆大霉素的壳聚糖微球粉末,并使其铺散于多孔钛层表面后进入孔内.经水润湿后,微球在孔内团聚并被固定于孔内.实验结果表明:水浴振荡试验7 d(100 r/min, 37 ℃)后, 80%~83%的微球仍位于多孔钛层内,微球-多孔钛复合物表现出初期(24 h)快速释放和后期( 24 h)缓慢释放;金黄色葡萄球菌培养48 h后,多孔钛与载庆大霉素微球的复合物产生了抑菌圈. 

Microsphere Agglomeration Technique for Drug Release from Porous-Coated Ti

A microsphere agglomeration technique incorporating gentamicin in porous-coated Ti was used to overcome technical disadvantages associated with available drug-release techniques for bone implants. Chitosan microspheres containing various concentrations of gentamicin were prepared by a water-in-oil emulsion method and lyophilized to dry powders. The powders were then spread on porous-coated Ti, and wetted with water to promote their agglomeration after they enter into the pores by gently tapping the samples. Microscopical analyses revealed that, the microspheres formed submilllimeter-sized agglomerates and entrapped in the pores. After immersion in shaking water bath (100 r/min, 37 ℃) for 7 d, 80%-83% of the agglomerates were retained in the coating, suggesting a reasonable entrapment stability. The microsphere-porous Ti complexes showed a rapid drug release in 24 h followed by a prolonged slow release. After coculture with Staphylococcus aureus for 48 h, the porous Ti carrying gentamicin-loaded microspheres produced clear inhibition zones, confirming its In vitro antibacterial activity.