本論文內容為開發微波輔助合成反應，探討以快速及高效方式合成甲基丙烯酸明膠 (gelatin methacrylate, GelMA) ，並結合幹細胞外泌體 (exosomes) 於製備聚二氧乙基噻吩:聚苯乙烯磺酸〔poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, PEDOT:PSS〕 系之可光聚合固化導電水凝膠，隨後探討其於心肌組織工程之應用。
關於GelMA合成方面，研究導入核磁共振及三硝基苯磺酸之比色法分析修飾率可達91%。隨後，以GelMA為光聚合水凝膠的主體，摻入聚二氧乙基噻吩:聚苯乙烯磺酸(poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, PEDOT:PSS)，導電高分子能提升水凝膠導電度，利於心肌組織周圍之電訊號傳遞，再加入光起始劑苯基-2,4,6-三甲基苯甲酰亞膦酸鋰 (lithium phenyl-2,4,6-trimethylbenzoylphosphinate, LAP) 將水凝膠以紫外光交聯聚合，並且提升機械性質使材料符合在心臟的楊氏模數範圍內。材料分析方面，我們導入黏度、光固化程度、機械性質及離子導電度等材料特性的綜合評估，以尋找出最佳化的混摻比例。以大鼠心肌母細胞H9c2做為評估模型進行細胞死/活染色、細胞活性測試及溶血率實驗證實材料的生物相容性，並將永生化骨髓幹細胞 (IBMSC) 之胞外泌體 (exosomes) 進行尺寸管柱層析法 (size exclusion chromatography, SEC) 純化， IBMSC的exosomes有助於刺激新生血管形成，並可抑制炎症反應，從而改善缺血性損傷後的心臟組織，期許因心肌梗塞 (myocardial infarction, MI) 造成的部分組織壞死能在此導電水凝膠添加exosomes的建立下提供修復心肌組織的新穎辦法，利用於治療心臟缺血性損傷並改善心肌纖維化的影響。

This research develops a microwave-assisted synthesis reaction to investigate the rapid and efficient synthesis of gelatin methacrylate (GelMA) in combination with stem cell exosomes for the preparation of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-based photopolymerizable conductive Hydrogels for myocardial tissue engineering, and then explores its application in myocardial tissue engineering.
Regarding the synthesis of GelMA, the study introduced NMR and colorimetric analysis of trinitrobenzene sulfonic acid, which showed a modification rate of 91%. Subsequently, GelMA was used as the main component of the photopolymerized hydrogel, and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was added, which is an electrically conductive polymer that can enhance the electrical conductivity of the hydrogel and improve the transmission of electrical signals around myocardial tissues. In addition, lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) was added as a photo initiator to crosslink the hydrogel with ultraviolet light and enhance the mechanical properties so that the material could fit into the Young's modulus range of the heart. For the material analysis, we introduced a comprehensive evaluation of the material properties, such as viscosity, light-curing degree, mechanical properties, and ionic conductivity, in order to find the optimal mixing ratio. Rat cardiomyoblast H9c2 was used as the evaluation model to confirm the biocompatibility of the materials by Live/Dead assay, cell viability test, and hemolysis test, and the exosomes of immortalized bone marrow stem cells (IBMSC) were purified by size exclusion chromatography (SEC). The exosomes of IBMSC help to stimulate neovascularization and inhibit inflammation to improve cardiac tissues after ischemic injury, and it is expected that partial tissue necrosis due to myocardial infarction (MI) can be repaired with the addition of exosomes to this conductive hydrogel, providing a novel approach to repairing cardiac tissues by utilizing the exosomes in the treatment of cardiac ischemic injury. It can be utilized for the treatment of ischemic heart injury and to ameliorate the effects of myocardial fibrosis.

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