促進骨再生之介孔生物活性玻璃支架作為藥物控制釋放載體之研究

Bone-regenerative Mesoporous Bioactive Glasses Scaffold with Drug Controlled Release

呂沛珊(Pei-Shan Lu)

指導教授 ： 石啟仁

高雄醫學大學/藥學院/香粧品學系碩士班/碩士(2011年)

摘要

介孔生物活性玻璃支架挾其高比表面積、兼具巨孔（200−400 μm）以及介孔（2∼50nm）、孔洞界面化性可修飾以及高骨再生活性等優勢，為極佳之骨植入材與藥物載體之候選材料。本研究將介孔支架作為促進骨組織再生之植入材，進行體外活性測試，並包覆健大黴素，達到藥物局部控制釋放之目的。
以氮氣吸/脫附曲線和穿透式電子顯微鏡觀察介孔結構，介孔支架具有高比表面積、孔洞體積特性，其比表面積、孔洞體積、孔洞大小分別為 328.7 m2/g、0.71 cm3/g、7.3 nm，且為均一規則通道排列。將介孔支架做生物評估，證實無細胞毒性，且貼附性良好，可幫助骨細胞進行分裂及分化。
介孔支架做為健大黴素之載體，經與藥物溶液攪拌時間24h後，具最大藥物載入量與包覆率，其值分別為19.2 mg/g以及31.1%；相對於不含介孔之玻璃支架而言；介孔支架藥物吸附量較高且釋放速率也較緩慢。
探討不同藥物起始濃度對介孔支架做為載體的影響: 濃度越高，包覆率下降，藥物載入量上升，且於最高藥物起始濃度 ( 50mg/ml ) 有最大藥物載入量為39.9 mg/g。其釋放行為在較高濃度下呈兩階段性釋放趨勢，在24 h前為快速釋放曲線，24~672 h呈現持續緩釋放行為，符合Higuchi動力學釋放模式。

關鍵字

介孔生物活性玻璃 ； 健大黴素 ； 藥物控制釋放

並列摘要

Mesoporous bioactive glasses scaffold (MBGs) possess a high specific surface area, and exhibits macropores (about 200−400 μm) and mesopores (2-50 nm) structures. Pore wall functionalized and enhancing bone-regenerative ability are the other advantages of MBGs. For these reasons, MBGs is considered to be a candidate for two main uses, bone tissue engineering and drug controlled delivery system. The purpose of this study is to confirm bioactivity of MBGs by in vitro tests and also as a gentamicin carrier to control drug release.
MBGs had been constructed by N2 adsorption/desorption and transmission electron microscope exhibits… a large specific surface area ( 328 m2/g ), pore volume ( 0.71 cm3/g ) and a uniformly distributed pore size ( 7.3 nm ), For comparison, in vitro tests results strongly suggest that MBGs is noncytotoxic, better cell affinity than non-mesoporous bioactive glasses scaffold (BGs) and can help cells division and differentiation.
The loading content and drug loading efficiency of MBGs are significant than BGs, and the values are 19.2 mg/g and 31.1%. It also been suggested the release rate of MBGs is much slower than BGs.
Loading efficiency and content are depends of of initial concentration. The largest amount of drug adsorption was 39.9 mg/g. The release curve exhibits a two- step release behavior, and fit Higuchi model. It also indicates that gentamicin burst-releases initially for a duration of 24 hrs, and then constantly slows released.

並列關鍵字

Mesoporous bioactive glasses Scaffold ； Gentamicin ； Drug controlled release

參考文獻

參考文獻

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