以簡易方式製成具微皺摺結構之導電高分子薄膜以誘導類神經細胞之分化

A facile method to fabricate a micro-wrinkled poly (3, 4‐ethylenedioxythiophene) promoting PC12 cells neural differentiation through electrical stimulation

林芷苓(Chih-Ling Lin)

指導教授 ： 游佳欣

國立臺灣大學/工學院/化學工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201904353

摘要

隨著組織工程的發展，治療神經系統受損的方法已經進入新的世代。許多研究團隊致力於以創新合成方式製成生醫材料以模擬人體中的微環境，除此之外，細胞的生物測試也被納入研究的項目之一，以測試生醫材料的有效性。
在微環境中，細胞會受到化學及物理性因素影響而有不同的表現。其中一個重要的決定性因素就是細胞外間質，值得注意的是帶有微結構的表面也能夠深深地影響細胞。除了將基質做改質之以外，也能夠利用物理方面的刺激影響細胞。在這些刺激當中，電刺激在神經分化上扮演著重要角色。然而，製造具有圖樣之導電表面常常是高時間成本或所費不貲，在本研究中，我們將提供一個簡易的方式製造帶有微皺褶結構且具導電特性的薄膜以誘導細胞神經分化。
我們選用PEDOT:PSS導電高分子作為薄膜的主成分，這是因為相對於其他導電高分子，PEDOT:PSS具有更高的導電性以及低細胞毒性，再者，PEDOT:PSS在細胞培養液中能夠有強烈的離子交換作用，進而促進細胞的增生。
在已拉伸的PDMS基質上均勻塗佈導電高分子於表面，在釋放應力的瞬間，微皺褶結構因為壓縮力而產生。本實驗中我們共測試了0%、 20%以及40%的組別，並對其做了表面材料分析以及生物測試。

關鍵字

大鼠腎上腺嗜鉻細胞瘤細胞 ； 導電高分子 ； 微皺褶結構 ； 表面溝槽 ； 神經分化 ； 電刺激

並列摘要

The treatment of nerve injuries has taken a step to another stage with the development of tissue engineering. Along with the novel synthetic strategy, different kinds of biomaterials have been devised to mimic the microenvironment in the human body. Also, cells are incorporated with the scaffolds to enhance the efficacy.
Cells’ performance can be modulated by chemical and physical features in the microenvironment. A crucial determinant of cell behavior and function is the extracellular matrix (ECM). It is worthy to notice that the structural features of the ECM can profoundly affect cell performance. Beside the biophysical properties of the substrates, cells can also sense and respond to a range of physical stimuli.
Among these stimuli, electrical stimulation is an especially important factor for neural differentiation. However, the fabrication of a conductive surface with the pattern is time-consuming or high costs. Here, a facile method for patterned and conductive substrates was provided.
PEDOT:PSS was elected as the conductive composition of the biomaterials in this research. Comparing to other conductive polymers, PEDOT:PSS possesses high electrical conductive and low cytotoxicity. Moreover, owing to its charge can strongly exchange with the culture medium, PEDOT:PSS is capable of promoting cell proliferation.
A micro-wrinkled film was fabricated by spin-coating PEDOT:PSS onto the pre-stretching PDMS substrate. The stretching ratio of 0%, 20%, and 40% was applied to further investigation. As the stored strain was released, a compression force would employ on the PEDOT:PSS film and the micro-wrinkles were formed. The corrugation was highly aligned, providing a suitable micro-structure for neuron extension. Moreover, electrical stimulation could be supplied via PEDOT:PSS films, introducing cells to neural differentiation.
The properties of PEDOT:PSS films with different pre-stretching ratio were investigated, including the surface topography, hydrophilicity, surface element analysis, and the electrochemical feature. Furthermore, for the bio characterization of the films, PC12 cells were seeded onto the PEDOT:PSS films and the cells’ performance, including cell morphology and gene expression, was examined.

並列關鍵字

PEDOT:PSS ； micro wrinkles ； topography ； PC12 cells ； neural differentiation ； electrical stimulation

參考文獻

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