實行三維細胞抓力顯微術所需考慮之因子

Working toward three-dimensional traction force microscopy

艾玉琪(Yu-Chi Ai)

指導教授 ： 高涌泉

國立臺灣大學/理學院/物理研究所/碩士(2016年)

https://doi.org/10.6342/NTU201610094

摘要

利用彈性基質中螢光粒子影像得到基質形變為基礎的細胞牽引力顯微術已有許多二維上的結果，但有鑑於細胞在自然中往往存在於三維空間，因此我們嘗試利用可調控機械性質的彈性膠體來製作空間對稱的圓洞讓細胞生長，並利用共軛焦顯微鏡來擷取三維立體影像。但因為活體細胞實驗的要點是提供適合細胞生存的環境，因此環境的加溫會造成影像拍攝過程中，從鏡頭到顯微鏡機身的熱漲冷縮效應，導致最後三維影像在垂直平面影像的方向上有嚴重的焦點面偏移，使得無法依據影像量化出精準的位移。為了能在z方向達到1 μm以下的解析度，我對顯微鏡系統做溫度控制，以自家顯微鏡為例子建造一個控溫的顯微鏡系統，並測試此溫控系統的效果能否解決影像偏移的影響，最後由不同加熱方法來估算出鏡頭部分溫度變化造成焦點面偏移的量值。

關鍵字

共軛焦顯微鏡 ； 細胞牽引力顯微術 ； 溫度穩定 ； 焦點偏移

並列摘要

Many results in cellular traction force microscopy (TFM) based on the flat matrix deformation determined by fluorescent marker displacement has been produced. Cells, however, are naturally live in three-dimensional environment, so we tried to make a substrate contain symmetrical spherical hole with tunable curvature to measure traction force. We use confocal microscope to image live cells. In order to carry out live cell imaging, the crucial factor is the heated environment for cell to live. The temperature fluctuation produced in the optical system made focus plane drift caused by the thermal expansion of lens or materials. In order to determine marker displacement in sub-micrometer scale, I did the temperature control experiment. I built a temperature-controlled microscope system by using our own microscope, and tested whether thermal drift effect was eliminated. Finally, I tried different heating methods to estimate the thermal drift quantity from the temperature increasing of objectives.

並列關鍵字

Confocal microscope ； live cell imaging ； temperature stability ； focus drift

參考文獻

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