對於復雜、困難或更俱生物學意義的研究課題，在空間中創造三維、多層、可移動的結構是需要發展的技術。光聚合水凝膠材料具有結構可變性和生物相容性的特點，非常適合製造這些複雜的微結構。在這項工作中，我們開發了一種稱為薄膜光刻的方法。通過使用螢光顯微鏡的紫外光在特殊設計的薄膜晶片（PTF晶片）內光聚合水凝膠微結構（聚（乙二醇）二丙烯酸酯，PEGDA 和明膠甲基丙烯酰，GelMA）。PTF 晶片的設計概念是基於紫外光的折射和光衰減所考量的。氧通過多孔 PDMS 材料擴散並抑制水凝膠光交聯。然而，PTF 晶片內微流道側壁內的氧會阻礙光聚合併導致抑制層的形成。在微通道中，我們集成了不同的 PDMS 微結構，通過紫外線照射形成基於水凝膠的微結構和抑制層。也觀察到氣泡在紫外光照射下的水凝膠微結構形成具有相似的影響。之後，我們將水凝膠與磁粉結合製成磁性水凝膠塊。將磁性水凝膠塊和包埋細胞的水凝膠塊交聯並驗證其中的細胞活力。混和10%GelMA與3%PEGDA的水凝膠塊，曝光後的細胞活力還有78%。之後，將磁鐵懸停在磁性水凝膠塊頂部的薄膜上，從而吸引或拖動磁性水凝膠。在這項工作中，通過 PTF晶片上的薄膜，我們可以操縱磁性水凝膠塊並將三塊水凝塊組裝整合成六邊形肝小葉圖案。最後，將此PTF 晶片被放置培養箱。HepG2細胞與3T3細胞被包埋在水凝膠中且共培養。培養液的白蛋白與尿素分泌被檢測。在第四天，共培養組的尿素的分泌物比控制組高出44.9%。

With complex, difficult, or more biologically meaningful research topics, it is developable and indispensable to create three-dimensional, multi-layered, movable structures or a variety of cells in space. Photopolymerized hydrogel materials have the characteristics of structural variability and biocompatibility, which are very suitable for manufacturing complex microstructures in biotech applications. In this research, the method named thin-film photolithography was developed by using the fluorescent microscope to form photopolymerized hydrogel microarchitectures (poly (ethylene glycol) diacrylate, PEGDA and Gelatin Methacryloyl, GelMA) within the polydimethylsiloxane (PDMS) thin-film chip (PTF chip). Here the design principle of our PTF chips is based on the physical phenomenon of refraction and ultraviolet (UV) light attenuation. However, oxygen within PDMS walls impedes the photopolymerization and causes the formation of the inhibition layers with oxygen diffusing through the porous PDMS materials and inhibiting the hydrogel photocrosslinking. In the microchannel, we integrated different PDMS microstructures to form hydrogel-based microstructures and the inhibition layer via UV light exposure. It was observed that the bubbles have a similar effect on the hydrogel structure formation with respect to the UV light exposure. After that, we combined the hydrogel with magnetic powder to make a magnetic hydrogel block. Cross-linked the magnetic hydrogel block and the hydrogel block with embedded cells and verified the cell viability in it. The hydrogel block mixed with 10% GelMA and 3% PEGDA has 78% cell viability after exposure. Finally, hover the magnet on the thin-film on the top of the magnetic hydrogel block, thereby attracting or dragging the magnetic hydrogel. The formation of hydrogel microstructures developed in this work differs from those exposed by the transparency mask and can be applied to the fields. Through the thin-film on the PTF chip, we can manipulate the magnetic hydrogel block and integrate it into a hexagonal liver lobule pattern. Finally, the PTF chip was placed in the incubator. HepG2 cells and 3T3 cells were embedded in a hydrogel and co-cultured. The secretion of albumin and urea in the culture medium was tested. On the fourth day, urea secretion in the co-culture group was 44.9% higher than that in the control group.

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