以光聚合技術建構具生物複合動力之水膠摺疊結構

Abstract

能夠隨時間做四維形狀變形(4D shape morphing)的機制其廣泛展現在不同領域中，像是軟性機器人與生物合成致動器，各團隊利用獨有的技術讓材料本身產生對外在環境的響應，或是透過刺激生物組織讓其所依附的基材變形。因此，本研究提出以正向光聚合摺紙技術為結構本體，並透過依附在其上方，可經電刺激收縮的肌肉組織來控制這個水膠摺紙結構。我們驗證以PEGDA700水膠所製作的正向光聚合摺紙，是否能夠在液相環境中對溫度產生自折疊的響應，並對有光交聯梯度的結構產生異相的脫水反應進行確認及優化。而為了達到可以用遠程照光的方式，對帶有不同光吸收劑的水膠摺紙結構進行可編程的折疊，因此本研究測試在水膠中加入不同光譜的光吸收劑，而因為水膠摺疊結構的成形為紫外光固化，因此觀察不同濃度且不同光譜的光吸收劑，在不同曝光能量下的成形後，其對所能呈現出的彎折效果進行討論。此外，本研究透過適當的架設，結合電控微流體平台與正向光聚合摺紙兩者的技術，製作出複雜且具編碼粒子的異質水膠摺紙。本研究也嘗試在水膠摺紙結構上貼附分化後能以電刺激產生收縮力的骨骼肌肌肉組織，試著排列成長中的肌小管，將包埋骨骼肌母細胞的GelMA水膠進行排列，以增加分化後的肌小管成形，最後也透過免疫螢光染色來確認其形態，說明電刺激後細胞的收縮表現。在未來，本研究的摺紙結構可以與能夠由NFC讀取器控制的NFC芯片的柔性電路板集成在一起，以感應產生的電驅動附著在水膠摺紙結構上的肌肉細胞。

The mechanism of 4D shape morphing over time has been studied in different fields. For example, various technologies have been investigated to build soft robots and biosynthetic actuators based on materials responding to the external environment or addressable biological tissues attaching on deformable structures. Here we constructed a hydrogel origami with frontal photopolymerization technology and controlled it with biohybrid power with attached muscle tissues contracted by electrical stimulations. We verified the fabrication of PEGDA700 origami with frontal photopolymerization and tested folding at varied environment temperature in the liquid phase. We confirmed and optimized the folding on the structures with photocrosslinking gradients. To achieve the goal of driving the origami with light illumination, different photoabsorbers were tested for driving with various spectrums. The bending angle of the test hinges containing photoabsorbers with different concentrations driven with different spectrums under different exposure energy were discussed. In addition, an electromicrofluidic platform was combined with frontal photopolymerization to produce complex heterogeneous hydrogel origami structures with programmable embedded particles. We also tried to adhere differentiated skeletal muscle tissues to generate contraction force by electrical stimulation on the hydrogel origami structure. We attempted to arrange the growing myotubes through arranging skeletal myoblasts in GelMA hydrogels to increase the formation of myotubes after differentiation and thereby to increase the contractility. The morphology of myotubes after culturing was confirmed by immunofluorescence staining, explaining the contractility of cells after electrical stimulation. In the future, our origami structure can be integrated with a flexible circuit board containing an NFC chip controlled by a reader to electrically drive the muscle cells attached on hydrogel origami structures.