以電氣紡絲製備奈微米纖維狀支架及其對細胞行為之影響

Fabrication of nano/micro-fibrous scaffolds by electrospinning and its cell behaviors

胡信泰(Hu Hsin-Tai)

指導教授 ： 曾厚

臺北醫學大學/口腔學院/生物醫學材料研究所/碩士(2005年)

摘要

眾所皆知胞外基質(Extracellular Matrix, ECM)，在活體中伴演著左右細胞行為的重要角色。而ECM是由基底層(basement membrane)與許多相互交聯網狀結構的蛋白質和多醣所組成，且這些網狀纖維結構大多如奈米般的細小；因此如何以人工方式製備奈米級(nano-scaled)纖維結構，應用於組織的修復與再生，顯得格外地重要。 本研究以生物可吸收性材料，聚左乳酸(PLLA)與聚丁烯琥珀酸己二酸共聚物(PBSA)為原料，並以電氣紡絲(electrospinning)為手法，製備成各種不同型態的纖維狀三維支架(fibrous scaffold)。在PLLA的實驗結果發現濃度與纖維直徑成正比，電壓與纖維直徑成反比，並用SEM計算這些纖維，平均纖維直徑大多落在在1?10μm，尚未達奈米結構。在PBSA的部分，因分子糾結能力低，在10與15w/v%時不論在何種電場作用下，都無連續纖維出現，直至在20w/v％才有出現連續纖維，纖維直徑約5μm。 在細胞貼附與增生實驗部分，PBSA比PLLA更有助於細胞貼附，這樣的情況主要來自於PBSA(contract angle=59.12°)比PLLA(contract angle=72.85°)的親水性高，有利於細胞進行延展 (spreading)。PLLA-ES(electrospun scaffold)比PLLA-CS(casting film)細胞貼附量多了60％；PBSA-ES也比PBSA-CS多了47％，證實三維狀支架比二維纖維支架有利於細胞貼附。PLLA-nano-ES比PLLA-ES多了23.5%，顯示奈米纖維狀支架比微米佳。 細胞增生部分，以PLLA-ES，PBSA-ES與PLLA-nano-ES 三種材料而言，卻是PLLA-ES的數量比其他兩種佳。主要的因素，可能為PLLA-ES的孔洞率為67.7%，PBSA-ES為56.22%，PLLA-nano-ES為45.42%，因為孔洞率的限制，使得細胞增生後空間性變得狹隘與擁擠，因此產生PLLA-nano-ES比PLLA-ES在增生表現來的不佳。

關鍵字

胞外基質 ； 聚左乳酸 ； 聚丁烯琥珀酸己二酸共聚物 ； 電氣紡絲 ； 纖維狀支架

並列摘要

It’s well known that in the living system, the extracellular matrix (ECM) play an important role in controlling cell behavior. The ECM is composed of a basement membrane(BM) and complex cross-linked network of proteins and glycosaminoglycans(GAGs) , and those non-woven fibre architecture are almost similar to nano-scale. It is therefore important to know how to fabricate an artificial nano-scaled fibrous structure for use in organ repair and tissue regeneration.. In this study, we used bioresorbable polymer Poly L-lactic acid (PLLA) and Poly butylene succinate-co-adipate (PBSA) fabricated various three-dimensional fibrous scaffolds by electrospinning. First, in PLLA electrospun mechanism results that showed the solution concretion had the direct ratio with average fiber diameter and electric field intensity have the inverse ratio. The average fiber diameter of fibrous scaffolds were almost at 1~ 10μm, that had not reached nano-scale structure in vivo like ECM yet. In another polymer (PBSA) electrospun mechanism showed that low concretion (10, 15w/v %) was without continuous fiber appearance in various voltage, until the 20w/v% appeared continuous fiber that average fiber diameter was 5μm. With regards to cell attachment and cell proliferation, cells attached more on the PBSA electrospun scaffold than on the PLLA electrospun scaffold. This was due to the higher hydrophilic property of PBSA (contact angle = 59.12?) compared to PLLA (contact angle = 72.85?) which facilitated cells to undergo spreading. The PLLA-ES (PLLA- electrospun scaffold) showed 60% more cell attachment than the PLLA-CS (casting film).On the other hand, the PBSA-ES scaffold exhibited 47% more cell attachment compared to the PBSA-CS scaffold. The above results confirmed that three dimensional (3D) scaffold was able to facilitate cell attachment more than two dimensional (2D) matrix. The PLLA-ES scaffold showed a better performance in terms of cell proliferation compared to the PBSA-ES and the PLLA- nano-ES scaffolds. This may be due to the difference in porosities of the materials; PLLA-ES: 67.7%; PBSA-ES: 56.22%; PLLA-nano-ES: 45.42%. Because of the limited porosity, available space was insufficient for continuous cell proliferation.

並列關鍵字

Extracellular matrix ； Poly L-lactic acid ； Poly butylene succinate-co-adipate ； Electrospinning ； Fibrous scaffold

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