本研究探討利用電泳與胞膜電穿孔實驗，來增加基因轉殖晶片上特定區域的轉殖效果，胞膜電穿孔是一種讓細胞膜外的物質進入細胞膜內的技術，其原理利用電脈衝所形成的電場，使細胞膜表面造成可逆性的電崩潰，產生瞬間的微小孔洞來使物質進入，實驗上採用pEGFP-N1質體，在晶片上轉殖進入成骨細胞(MC3T3E)中。
本實驗利用微機電製程技術在玻璃底材上製作出薄膜電極，並利用高分子材料定義細胞反應區大小，在胞膜電穿孔前將DNA注入且蓋滿反應區，利用上下電極所產生的電場來驅動帶負電的DNA，讓DNA聚集在通正電的指叉狀晶片電極上，使DNA濃度提高，接著進行胞膜電脈衝轉殖實驗。在電泳過程中，利用一維解析解與二維數值模擬來探討DNA濃度的變化，由研究的結果顯示，在電脈衝之前，DNA在晶片表面上的濃度可增加到原本的數千倍，因此，藉由DNA電泳後濃度的提高來增加傳統電脈衝的轉殖效果，本實驗成功地利用電泳技術提高胞膜電穿孔晶片的轉殖效率。

The present paper investigated the site-specific enhancement of in vitro gene delivery using electrophoresis and electroporation microchips. Electroporation is a technique that introduces foreign materials into cells by applying impulses with an electric field to create multiple transient pores in the cell membrane through a dielectric breakdown of it. The pEGFP-N1 plasmids were transfected into osteoblasts cells (MC3T3E) on the microchip.
The electroporation chip with thin film electrodes were fabricated on a glass slide using microfabrication technologies. The region of cell culture cavity defines by rectangular macromolecular compounds. The electric field for DNA attracting results in the increment of DNA concentration on the surface of these powered electrodes. Then the electric power was switched to the interdigital electrodes to continue the electroporation process. The DNA concentration during electrophoresis on the microchip was investigated by one-dimensional steady-state approximation and two-dimensional transient simulation in this study. The study demonstrated the DNA concentration close to the cell surface increased up to several thousands-fold before electroporation so that improve the transfection efficiency comparing to the conventional electroporation. The present work successfully enhanced the site-specific transfection utilizing the attracting electric field on the electroporation microchip.

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