| 摘要: | 近年來，由於健康意識觀念抬頭，生醫工程屢屢被關注。因此組織工程相關研究成為近期熱門研究主題之一，其與積層製造結合成為3D 生物列印技術，在生物支架列印方面不僅解決複雜圖形之製造，也同時模擬天然細胞外基質以提供細胞良好的生存環境。
常見的生物列印機都以單種列印方式製作支架，若以製作複雜皮膚結構，例如: 燒燙傷皮膚及糖尿病患者慢性潰爛之皮膚等…表皮及真皮層損傷的案例，較難呈現出真實的樣貌，導致組織生長不良。因此，本研究以混和列印為目的，將兩種不同的列印方式集成於生物列印機上，並依照不同的結構特性選擇適合的沉積方式，以適應複雜的支架需求。硬體方面，開發包含氣動擠出式及微型閥噴墨式的多噴頭置換模組，並驗證兩個噴頭疊加列印的平均偏差值，確保對位精度以適應複雜的支架需求。軟體方面，使用C#程式語言控制置換流程、高度校正及溫度監控，達到機台自動化的目的。
本研究以Gelatin 及Pluronic F-127 混合而成的熱敏性複合水凝膠作為生物墨水，並使整體列印溫度控制在37℃，以便未來進行細胞培養的實驗。在噴頭方面也發展緊湊型加熱套，除了將加熱區域極小化以改善加熱效率，也可以即時監控針頭溫度及沉積的環境溫度，防止噴頭堵料及維持材料流變性質。本研究除了分析兩種列印方式的列印參數對於股線線徑之影響，在支架列印的部分也利用氣動擠出式沉積25 層約2.5mm 高的支架以模擬真皮組織，並由顯微鏡量測其孔洞的平均直徑約為0.1mm，再利用微型閥於支架表面沉積0.5mm 高的生物墨水以模擬表皮組織，最終製作出3mm 高之皮膚支架。若未來列印含細胞生物墨水時，不僅能使細胞更為均勻，也能更仿真成為皮膚結構。;Nowadays, as the concept of health awareness rises, biomedical engineering has been brought to public attention. Therefore, tissue engineering has become one of the hottest research topics. It combines with additive manufacturing to become 3D bioprinting technology, which not only solves the manufacturing of complex scaffold but mimics the natural extracellular matrix to provide a good living environment for cells.
Common Bioprinter used to manufacture scaffold with single printing mode, if it manufactures complex skin structures, such as burned skin and chronic ulcerated skin that epidermis and dermis are damaged. It is difficult to mimic the real appearance and also make tissues grow worse. Therefore, the purpose of this research is to integrate two different printing methods on bioprinter and choose the appropriate deposition method according to different structural characteristics to meet the needs of complex scaffolds. In terms of hardware, a multi-nozzle exchange module including pneumatic extrusion and micro-valve inkjet is developed.
Moreover, the average deviation value of the two nozzles superimposed printing is verified to ensure the accuracy of alignment that meets the complex scaffold requirements. In terms of software, the C# programming language is used to control the exchange process, height calibration, and temperature monitoring to achieve the purpose of machine automation.
In this research, a thermosensitive composite hydrogel composed of Gelatin and Pluronic F-127 was used as a bio-ink, and the overall printing temperature was controlled at 37°C for future cell culture experiments. In the aspect of the nozzle, a compact heating sleeve has been developed, which can instantly monitor the temperature of the needle and the ambient temperature of the deposition level to prevent the nozzle from clogging and maintain the rheological properties of the material. In addition to studying the printing parameters of different printing methods, this study also used pneumatic extrusion to deposit 25 layers of about 2.5mm high scaffold to mimic dermal tissue, and use a microscope to measure the diameter of the scaffold hole is about 0.1mm. Furthermore, use the microvalve to deposit bioink
with 0.5mm high on the surface of the scaffold to mimic the epidermal tissue, and finally produce a 3mm high skin scaffold. If the bio-ink containing cells is printed in the future, it will not only make the cells more uniform, but also more simulation to become a skin structure. |
