以電氣紡絲法製備PLA╱PCL小管徑人工血管支架之性質及其細胞生長研究

Abstract

本研究以聚乳酸(PLA)與聚己內酯(PCL)為材料，依不同比例進行溶液之調配，藉由不同的收集速度以電氣紡絲法製作出纖維排列具有不同方向之小管徑人工血管細胞生長支架，支架內徑4.1mm，外徑5mm，壁厚0.45mm，並對製作出來的人工血管細胞生長支架進行表面結構之觀察及接觸角(親水性)、孔隙率(porosity)與機械性質之量測。另外動態植覆血管內皮細胞後進行靜態培養，觀測不同製作條件之人工血管細胞生長支架其細胞的生長情形與細胞活性，最後為了模擬人體的血流環境，對血管內皮細胞進行靜脈與動脈流速之動態培養，並觀察其細胞生長情形。 實驗結果發現纖維排列不具有方向性的人工血管細胞生長支架其孔隙率較高，在靜態與動態培養上其細胞數量都明顯較高，不過纖維排列具有方向性的人工血管細胞生長支架其細胞會沿著纖維方向生長而具有方向性。藉由不同比例的調配方式與收集速度確實可以製作出不同機械性質的人工血管細胞生長支架，可以視需求選擇調配比例與收集速度。

In this study, we mix polylactic acid (PLA) and polycaprolactone (PCL) solutions with different ratio for the purpose of electrospinning. The fiber were then collected under different speed for manufacturing small diameter artificial vascular scaffolds (inner diameter of 4.1mm, outer diameter of 5mm, wall thickness of 0.45mm). Vascular scaffolds fabricated this way showed different fiber orientations. Then we observed the surface structure and measured the contact angle (hydrophilic), the porosity and mechanical properties of the scaffolds. The vascular scaffolds were used for culturing endothelial cells under static and rotational state to find out the growth and activity of the cells. Finally in order to simulate the environment of the human body's blood flow, the cells were cultured under the flow velocity of the venous and arterial, and observe cell growth situations. The experimental results showed the cell numbers in static and dynamic state with random orientations of fibers are higher than ones with aligned fibers. This phenomenon might arise from the fact that scaffolds with random fiber orientation have higher porosity. However, the cells do grow along the fibers direction in the artificial vascular scaffolds with aligned fibers. The artificial blood vessel scaffolds with the different solutions mixture and collection speed have different mechanical properties. We can select the ratio of the solution and the collection speed as needed.