當細胞去貼附細胞外基質時，細胞會產生強烈收縮力去攀爬細胞外基質，使細胞拓展開來並且進行分化的作用，而細胞外基質的結構及強度會影響細胞的生理狀況及生物力學特性，當細胞生長時細胞外基質必須有適合的生長環境可以提供給細胞一個良好之生長條件。否則，即使細胞與植入物表面達成接觸，但是細胞卻無法在材料表面拓展開來，與材料之表面產生牢固的固定效果。在這種細胞骨架架構行為失敗的狀況下，細胞可能會朝細胞凋亡的路徑發展，而細胞力學行為相當複雜且重要。
　　
　　本研究利用微製程技術製作出一具有彈性的微柱狀陣列結構(micro-pillar arrays, MPA)，以量測細胞力學特性，並可透過不同微柱頂端的接觸面積瞭解細胞與基質間相互調控的生物力學機制。實驗中以聚二甲基矽氧烷(poly(dimethylsiloxane), PDMS)為基材，並且透過PDMS的製程加熱時間控制其楊氏係數(Young’s modulus)，其中楊氏係數利用動態機械量測儀與景深焦距量測方式相互實驗驗證，2 hr, 4 hr和6.5 hr的1:10 PDMS分別為1.53±0.023、1.74±0.012和1.68±0.018 MPa，此外在細胞力學量測方面，當細胞貼附在不同間距與機械強度的MPA上時，細胞開始生長、延展或移動，此時細胞所產生的收縮力會拉扯MPA結構並且會使微柱產生彎曲變形，透過光學系統對MPA頂端進行影像定位與分析，即可量化並追蹤細胞貼附或移動時所需的力學機制，並且透過細胞力學的微陣列力量感測系統平台可以定量出細胞每點的機械力，達成微觀測量細胞生物力學的特性，實驗中發現細胞會隨著貼附面積增加而增加其牽引力，並且細胞周圍所量測的值皆大於其中心位置的力量，其細胞中心力量分佈分別為12~115 nN，周圍力量分佈分別為55~259 nN，其中直徑25 μm微柱上細胞的力量分佈為124~302 nN。
　　
　　本研究中所設計之評估細胞力學的微陣列力量感測系統已製作開發完成，不但可透過製程方式調控微柱基材的強度，並且可成功定量偵測出纖維母細胞的力學行為。透過此技術平台可進一步探討細胞與基材相互間的機制研究，未來對於細胞力學研究可獲得更多資訊。

　　When cells adhere on substrate and process adhesion, extension, proliferation and migration, it is not only provides the chemical stimuli but also serves as a structural support to the cells. The chemical or physical characteristic of the substrate could influence the bio-physiological and biophysical functions of the cells. When cells contact with substrate and process extension and migration, some structural proteins (such as actin) could form the cytoskeleton in the cells and generate the contraction force in the cells. Meanwhile, substrate has to provide sufficient stress and growth environments to the cells. However, when substrate could not provide sufficient stress, cells adhere on the surface of the materials but could not extent on it. The insufficient stress may alter the construction of cytoskeleton and fail to generate the internal tension in the cells. Under losing of tensegrity, cells will process apoptosis. That will increase the importance in studying the generation of cell-mechanics and tensegrity.

　　In this study, we present an approach to manipulate and measure mechanical interactions between cells and their underlying substrates by using microfabricated elastomeric micro-pillar arrays (MPA). The substrates were prepared using poly(dimethylsiloxane) (PDMS). The heating time was controlled in order to obtain PDMS with different Young’s modulus, which was detected by both dynamic mechanical analyzer (DMA) and focus microscopy. The results of 1:10 PDMS at 2, 4 and 6.5 hr heating time is 1.53±0.023, 1.74±0.012 and 1.68±0.018 MPa, respectively. When the cells adhered on MPA of different space and mechanical strength, the contractile force produced from the cell growth, extension, and migration would cause structural change in MPA. The bending of the MPA was detected by optical system for image analysis. The mechanical strength of cell adhesion and migration of the MPA then could be quantified, and with mechanics-sensing plate, the mechanical strength on each cantilever could be obtained. We found that the traction force of the cells was increased with the adhesion area. Furthermore, the force measured on the outside of the cells was greater than the center. The center and outer forces of the cells was 12~115 nN and 55~259 nN, respectively. In addition, the force measured for the micro-pillar of diameter 25 μm was 124~302 nN.

　　The development of the force sensing array system for the evaluation of cell mechanical behavior was completed. The rigidity of the micro-pillar could be control during fabrication. The system could measure the mechanical behaviors of 3T3 fibroblast. With this system, the mechanical interactions between cells and their underlying substrates, which would be helpful in future cellular studies.

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