周邊神經再生是目前組織工程中最重要的課題之一，過去以導管設計與促進生長藥物為研究主題，但隨著細胞力學的發展，探討外在物理性刺激對周邊神經再生的影響逐漸受到重視。

本研究利用原子力顯微鏡進行單點斜坡動態測試，準確量測細胞黏彈力學特性。因傳統使用的彈性模型，如Hertz模型等，存在著不合理的假設，故本研究引入了類線性黏彈性模型，配合Bilodeau彈性模型估測出神經細胞的黏彈機械性質，並藉由模擬結果成功驗證僅使用彈性模型會造成楊氏模數的高估。本研究量測樣本為PC-12類神經細胞，量測細胞本體與軸突之機械特性，結果顯示本體楊氏模數為0.54±0.24 kPa，軸突之楊氏模數為4.95±2.52 kPa。此外，本研究利用免疫螢光染色影像觀察細胞骨架，證明細胞骨架分佈具有區域性，但量化後結果與楊氏模數分佈不完全一致，此結果顯示細胞骨架與細胞彈性特性並非絕對關係，日後若能加上環境控制系統，延長細胞生命，針對同一個細胞進行量測與免疫染色，可能使結果會更加準確。

本研究首次引入類線性黏彈性模型於細胞力學領域中，結果顯示此模型略優於線性黏彈性模型與彈性模型，相信於後續研究中此模型可以提供量測細胞黏彈機械特性的有效方法。

Peripheral nerve regeneration is one of the important issues in tissue engineering. In the past, it was focused on improvement of conduit design and drugs to promote cell growth. Cell mechanics researches have been developing rapidly in recent years and the effects of physical stimulations on growth of peripheral neural cells have attracted more researches.

The biomechanical properties of single and attached PC-12 neural cells and axons were measured by performing ramp and hold indentation experiments by using an atomic force microscopy (AFM). The existing elastic models of PC-12 cells were derived from Hertz theory which was based on an unreasonable assumption and the Young’s modulus was over estimated. In this study, to analyze the experimentally obtained relationship between force and indentation depth, quasi-linear viscoelastic (QLV) model and Bilodeau model were utilized. The results showed that the Young’s modulus of PC-12 cell body is 0.54±0.24 kPa and 4.95±2.52 kPa for axon. Immunofluorescent method was also employed to observe the cytoskeleton (CSK). The results showed the regional distribution of CSK and no direct relationship between CSK and Young’s modulus could be found.

In this thesis, the QLV model was first adopted for modeling the mechanics of living cells. The results showed that QLV model is more accurate than linear viscoelastic model and elastic model. QLV model may be served as an effective method for estimating viscoelastic properties of living cells. In the future, by constructing an environment control system to prolong life of cell may make possible mechanical indentation and immunofluorescent observation on the same cell and improve accuracy of the results.

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