本研究使用兩種天然單體所合成出來的聚癸二酸丙三醇酯(poly(glycerol sebacate),PGS)彈性體，其生物可降解性且富有良好的彈性，然而，對於製備出PGS奈米纖維有著一大挑戰，無論是PGS prepolymer，由於其分子量低，分子間的交纏程度不夠，或是交聯後的PGS彈性體，無法有合適的溶劑配製成電紡溶液，皆有著單獨電紡出PGS纖維之困難性。在本研究中使用客製化的同軸電紡裝置，透過已知可電紡之高分子材料做為外管帶出內管不可紡之高分子材料(PGS prepolymer)，製備出具芯/殼結構之電紡纖維薄膜，使用PLA做為外管材料因為其熔點能夠承受內管PGS交聯溫度，特別的是探討在外管溶液中添加PEO，在交聯之前將PEO移除，對於薄膜之影響。使用穿透式顯微鏡確認同軸纖維之芯-殼結構；掃描式顯微鏡觀察電紡薄膜的表面形態，添加PEO纖維直徑是減小的；移除外管材料的過程可以透過傅立葉轉換紅外線光譜來確認纖維薄膜的官能基，將纖維薄膜放入真空烘箱在不同的交聯溫度與時間進行交聯反應，使用單軸拉伸測試得知纖維薄膜的機械性質，與先前研究相同的是，隨著交聯溫度的提高與時間的增加，薄膜的楊氏模數與拉伸強度隨之上升，剛性(stiffness)增加；有趣的是，外管的PLA材料對於具PGS/PLA芯/殼結構之電紡纖維薄膜的機械性質來說扮演重要的角色，外管溶液為PEO/PLA混合溶液相較於純PLA是更有柔順性；提高內管溶液的PGS濃度，纖維薄膜的剛性增強，讓內管PGS有主導纖維薄膜機械性質之能力；最後以70% PGS為內管溶液，PEO/PLA混合溶液為外管溶液所製備具PGS/PLA芯/殼結構之電紡纖維薄膜移除外管PLA材料後，得到PGS電紡纖維薄膜，根據交聯的條件楊氏模數範圍約為0.47~1.03MPa，其機械性質有較佳的柔順性與彈性，能夠運於軟組織範圍中，並且證實以高度順向性的PGS纖維對平滑肌細胞有產生接觸引導(contact guidance)的能力，以此PGS纖維製作的組織工程支架，有著類似於細胞外基質的結構，有潛力可成為軟組織工程支架。

It is challenging to fabricate electrospun PGS nanofibers because of the poor electrospinnability of its prepolymer and fully crosslinked polymer the low molecular weight. In this study, coaxial electrospinning, which allows a non-electrospinnable polymer to be drawn by a electrospinnable polymer was used aiming at fabricate PGS nanofibers. PLA was used as shell material because it does not melt at PGS curing temperature confining PGS prepolymer in the core. Specifically, the effects of adding PEO in the shell solution were investigated; PEO was removed prior to curing. The fibrous membranes were cured in a vacuum oven at varying temperatures for different reaction time. Transmission electron microscopy was used to illustrate core-shell structure of the fibers. Scanning electron microscopy was used to examine the morphology of membranes. Fourier transform infrared spectroscopy was used to confirm functional group of the membrane after removing PEO and PLA shell. Mechanical properties of the membrane were examined by uniaxial tensile testing. The addition of PEO decreased the fiber diameter. Consistent with previous studies, we found that both the higher curing temperature and the longer duration of curing increased the stiffness of the membrane. We found that PLA appeared to play a role in the mechanical properties of electrospun PGS membrane. The electrospun core/shell PGS/PLA membranes fabricated with PEO/PLA mixture as shell material are more compliant. Moreover, increasing the PGS concentration in the core, the electrospun membrane became stiffer. The core seemed to dominate the mechanical properties of the membrane when 70% PGS was used as the core solution. Finally, electrospun PGS membrane with no PLA in the shell were achieved from the fibers fabricated with 70% PGS as the core solution and PEO/PLA mixture as the shell material. After the removal of PLA shell, PGS fibrous membrane was more compliant and had better flexibility. The Young’s modulus of electrospun PGS membrane was in the range of 0.47~1.03MPa, depending on curing conditions, which is similar to that of soft tissues. We also demonstrated by seeding smooth muscle cells on the membranes containing aligned fibers and found that they have potential of guiding cells alignment.

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