細胞排列技術是建構與活體相似、高複雜度組織和器官的重要基礎。雖然細胞排列的技術發展至今已經有一段時間，但是大多數排列細胞的方法都很複雜，有的還需要一些特殊儀器輔助。本研究利用磁力和光敏性水膠發展出一種簡單且有效率的細胞排列方法。首先，我們將聚乙二醇混合磁性微顆粒，再用光微影技術做出有特殊圖案的水膠磁塊。由於我們的曝光系統解析度大約150微毫米左右，因此無法做出太細微的圖案。此外，為了證實水膠磁塊能夠被磁力所控制，我們利用磁性探針去操控水膠磁塊，結果發現探針不必接觸磁塊，即可將它移動到任何特定的位置。接著，我們把水膠磁塊放入細胞培養盤中，並以磁鐵吸附定位。再把細胞放入培養盤內，細胞會貼附在未被水膠磁塊覆蓋的地方。待細胞貼附之後，我們再利用磁力將水膠磁塊移除。如此，就可以做出特殊的細胞圖案。如果放入第二種細胞到培養盤內，此些細胞會貼附於尚未佔據的空間，而產生由兩種不同細胞所組成的圖案。另外，我們也發現這種方法對細胞的毒性很低，幾乎不會影響到細胞生長，也不需修飾細胞，因此解決了別種細胞排列法常發生的限制。綜合以上實驗結果，我們認為這種細胞排列方法對於研究細胞生物學和組織工程而言是一項相當有用的技術。

Cell patterning techniques are the basis to construct in vivo-like complex tissues and organs. Although many cell patterning methods have been developed so far, most of them are either sophisticated or depend on special devices. Here, we present a simple and efficient cell patterning method which is based on magnetic force and photosensitive poly (ethylene glycol) diacrylate (PEG-DA) hydrogels. The PEG-DA hydrogel was made magnetic by mixing with magnetic microparticles and fabricated into specific patterns by photolithography. The resolution of this approach in microstructure fabrication was shown to be about 150 μm. In addition, the patterned PEG hydrogels can be manipulated by using magnetic force and transported to desired locations without direct contact with the magnetic probe. To create cell patterns, the magnetic PEG-DA blocks were placed into a cell culture dish and hold at a designated position with a magnet. Cells were then seeded on the areas not covered by the hydrogel and allowed to attach. After the cells were adhered tightly to the dish surface, the hydrogel was removed, again by magnetic manipulation. The second types of cells were then loaded into the culture dish to grow on the unoccupied areas to form heterotypic cell patterns. Using this method, many complex cell patterns can be generated with good resolutions. This method produces negligible effects on cell viability, thus eliminating potential cell harmful effects associated with other cell manipulation methods. Together, these findings indicate that this simple cell patterning method will be a useful tool in cell biology and tissue engineering.

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