本實驗使用孔徑大小25 μm的不銹鋼網作為基材，接著將不銹鋼網與多巴胺(Dopamine)單體放置在微鹼的溶液當中以在不銹鋼網表面形成奈米級的聚多巴胺顆粒，並在過程中摻入分支型聚乙烯亞胺 (Branched polyethyleneimine，BPEI)，再以EDC/NHS共價鍵固定法將海藻酸(Alginate)接枝在不銹鋼網表面，接著，同樣利用EDC/NHS共價鍵固定法修飾Protein G，再透過Protein G與Anti-EpCAM專一性抗體間的強親和力將其固定在表面，最後利用牛血清白蛋白(Bovine Serum Albumin，BSA)在表面形成抗沾黏層完成試片的製備，再結合自製的流體裝置進行各項循環腫瘤細胞與病患檢體中目標細胞的抓取，利用電化學方法進行定量分析，並在後端進行細胞培養以及利用海藻酸裂解酶(Alginate lyase)進行細胞的釋放。
從實驗結果得知，在利用電化學阻抗頻譜分別偵測5、10、25、50顆循環腫瘤細胞於流速1hr/3mL、1.5hr/3mL的條件下，阻抗變化有高度的正相關，R2值為0.9776，也透過DLD-1與Hela cells確認抗體之專一性。即使在10000顆Hela cells的情況下，電化學阻抗值也並未發生變化；此外，我們也將試片應用於細胞培養，細胞活性在第4天可達到341 %，遠高於在傳統培養盤上的184 %，在細胞培養3-4天後利用海藻酸裂解酶進行釋放也發現良好的細胞釋放效果。
在臨床結果的部分，在收集到的18名患者檢體中，3名第一期的患者皆沒有捕獲到循環腫瘤細胞，而4名第四期的患者抓取到之循環腫瘤細胞顆數皆在10顆以上，而病患之腫瘤大小與侵犯位置(T)數值與抓取到之顆數也同樣呈現正相關，在T1時抓取到循環腫瘤細胞的機率為0 %，T2為50 %，T3為78 %。在回診的案例當中，術前術後循環腫瘤細胞差值8顆的患者已確認復發，而差值0顆的則並未復發，顯示此試片可用於判別病人期數以及作為術前術後治療效果的指標。

In this experiment, we used a stainless steel mesh with a pore size of 25 μm as a substrate. The substrate and dopamine are placed in tris buffer to form polydopamine particles on the surface of the stainless steel mesh. In this process, the branched polyethyleneimine (BPEI) is added. And we used the EDC/NHS to graft the alginic acid (Alginate) onto the surface of the stainless steel mesh. Same as well, Protein G was modified on the surface through EDC/NHS. And we modified Anti-EpCAM specific antibody on the surface through the strong affinity between Protein G and Anti-EpCAM. Finally, we use bovine serum albumin (Bovine Serum Albumin, BSA) to form an anti-fouling layer on the surface to complete the preparation of the specimen. We builded a self-made fluid device combined with the specimen to capture the circulating tumor cells, using electrochemical methods for quantitative analysis. And we applied the specimen to do the cell culture and alginate lyase to release the cells.
The results show that when we used electrochemical methods to do the quantitative analysis for 5, 10, 25, and 50 circulating tumor cells under the flow rate of 1hr /3mL and 1.5hr/3mL, a high positive correlation was found in impedance changes. The specificity of the antibody was also confirmed through DLD-1 and Hela cells. Even 10000 Hela cells would not cause the impedance changes. In addition, we also applied the specimen to cell culture. The cell viability reached 341% on the fourth day, which was much higher than 184% on the normal cell culture flask. We also used alginate lyase to release the cells after 3-4 days of cell culture, and showed good cell release effect.
In the clinical results, we collected 18 patient sample. All of the stage I patient showed CTCs negative, when all stage IV patient show CTCs positive and the cell counts were more than 10. And the size of the cancer tumor and whether or not it has grown into nearby tissue (T) and CTCs showed a high positive correlation. T1 patient showed 0 % CTCs positive, T2 patient showed 50 %, and T3 patient showed 78 %. And we found that, patient with a difference of 8 CTCs after surgery have confirmed recurrence when patient with a difference of 0 have not. This result showed that this specimen can be used to determine the stages and treatment effect.

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