膀胱癌是我國近年男性十大癌症，為泌尿系統常見的癌症，並且手術後復發率極高，需要持續追蹤病情，目前常見的檢查方法為膀胱鏡，但是這種侵入式的方法容易造成患者不適，並且有尿道感染的風險，透過核磁共振或電腦斷層掃瞄醫療設備，呈現膀胱內部影像，則是相當耗時與高成本，因此發展新的檢查方法為重要課題。
過去癌細胞捕捉的研究成果尚未理想，主要受限於檢體(血液、尿液)中的細胞數量鮮少，導致細胞捕捉的難度相當高，即使嘗試不同檢測的方式，捕捉效率並無顯著提升，並且操作方法十分繁瑣、費時與昂貴。近年來，隨著微奈米結構與細胞行為的相關研究趨於成熟，已經有文獻證實微奈米結構，相較於平面基板或液相，能夠提高癌細胞的捕捉效率。
本論文使用金屬輔助化學蝕刻的方法，製作高深寬比矽奈米結構，具有簡易、快速與低成本的特點，而且基板為生物相容性良好的矽材料，利用結構進行細胞捕捉實驗，探討結構對於癌細胞與正常細胞的捕捉差異性，在4小時的培養時間，第三期膀胱上皮癌細胞(T24)的貼附率超100%，並且與正常膀胱上皮細胞(SV-HUC1)的貼附率比值高達3倍，對於癌細胞與正常細胞的捕捉結果有明顯區別，具有捕捉特定癌細胞的潛力。

In this study, we reported on cost-effective, simple and anisotropic etching approach to fabricate high aspect ratio silicon nanostructures using UV-nanoimprint lithography and metal-assisted chemical etching (MACE). After that, silicon nanostructures were served as cell capture substrates. Bladder epithelial cancer cells (T24) and Bladder epithelial normal cells (SV-HUC1) were separately soaked in PBS environment and incubated with different substrates for 2 and 4 hours. In particular, the cell attachment rate of T24 cells was over 100% on silicon nanostructures at incubation time of 4 hr. However, the cell attachment rate of SV-HUC1 cells was only 40%. It was obviously that cell capture substrates based on silicon nanostructures were demonstrated to exhibit efficient cancer cells capture. In the future, we will further improve the specificity of cancer cells capture and apply to clinical urine or blood examination.

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