鎂合金因具有良好力學特性及生物可降解性，降解成分可刺激骨細胞活性，適合應用在人工植體上，有機會取代目前臨床使用之不銹鋼與鈦合金，被視為第三代生醫材料。但生醫鎂合金由於抗腐蝕性差，動物實驗顯示鎂合金本身降解速率過快，導致植體表面析氫速度太高與增加周圍溶液 pH值，引起身體異常反應。鎂合金另一個問題是表面改質不易，很難利用現有表面改質方式獲得良好抗蝕並具有生物親和性表面。
本研究使用高溫反應器進行水熱處理，使試片表面生成均質與緻密之氧化物保護膜，提高試片基材抗腐蝕能力。而新式T-BAG 製程可有效的接枝上單分子膜，藉由單分子膜技術改變官能基，利用表面官能基獲得不同的性質，因此本研究融合此二種表面處理技術，並各別探討經表面處理後的鎂合金抗蝕性及生物相容性的變化。首先利用水熱處理方式在生醫用鎂合金表面生成氫氧化鎂保護膜，提供基材具有抗腐蝕能力，接續利用 T-BAG 法進行改質，獲得疏水性的保護，在模擬體液下進行電化學試驗及浸泡試驗結果中，各項耐蝕性的指標皆有隨處理步驟有順序性明顯上升，證明水熱複合單分子塗層的表面可以改善鎂合金之抗腐蝕性。在生物親和性測試中，以細胞毒性、細胞形態、細胞增生能力及蛋白質吸附量進行評估，各組別皆無明顯細胞毒性，其他項目皆有明顯改善的效果。經過表面處理後細胞貼附能力及增生效果大大提高，最後由蛋白質吸附實驗證實材料表面因官能基及疏水性的影響，提高蛋白質吸附能力並提供骨細胞更良好的生長環境。由上述結果，本研究所研究之鎂合金表面處理技術可有效應用於可降解性骨科植體。

Magnesium (Mg) and its alloys are new biomaterials which have been studied recently for hard-tissue replacement. The advantages of magnesium alloy compared to other metal traditionally used in implant, such as stainless and titanium alloy. Magnesium alloy have good mechanical properties and biodegradable. In addition, magnesium is an essential component in human metabolism, and magnesium is known to play an important role in the bone formation. However, owing to high electrochemical corrosion, the poor corrosion resistance of magnesium alloy hinders their use in clinical application. Thus, surface treatment is indispensable to improve their corrosion resistance and biocompatibility. Compared to Ca/P deposition and anodic treatment, hydrothermal treatment could form a uniform, adhesive and protective oxide film on the surface of magnesium. The oxide film could protect magnesium alloys from the aggressive attack in human body. By T-BAG method, the hydrothermal oxide film can be modified with hydrophobic monolayers. The designed tail groups and molecules can be selected to form T-BAG for specific applications, such as corrosion resistance and biocompatibility.
In this investigation, attempt will be devoted to apply hydrothermal treatment to grow protective oxide films of magnesium alloy. After hydrothermal treatment, biocompatibility and protective hydrophobicity could be achieved by grafted functional groups on oxide film by T-BAG method.
The electrochemical and immersion test(in R-SBF) results indicated that anti-corrosion behavior can be enhanced by hydrophobic tail groups (-CH3) on hydrothermal coating surface of plate-like architecture. All the results suggest that the hydrothermal / T-BAG coating can effectively protect the magnesium alloy.
And the biocompatibility of magnesium alloy and coatings was studied by using human osteoblast-like MG-63 cells. It was found that the MG-63 cells could grow well on the surface of hydrothermal/T-BAG coated AZ61 and the evidently cell proliferation rate were provoked by protein adsorption in culture medium. It was concluded that the hydrothermal/T-BAG coated magnesium alloy had good biocompatibility.

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