Development of Micro-grooved Silk Fibroin/Polyethylene Oxide Film Scaffolds for Neural Tissue Engineering Applications

Abstract

In the field of neural tissue engineering, intensive work is being done to develop alternative nerve guide channels with the new techniques offered by nanotechnology and biomaterials science. However, an ideal neural scaffold capable of mimicking the natural extracellular matrix, having an intraluminal channel structure, have suitable micro/nano patterns, can support neural cells and guide them has not been fully developed yet. The aim of this study is the use of electron beam lithography technique to obtain micro-grooved silk fibroin/polyethylene oxide (SF/PEO) film scaffolds with various channel widths (1 µm, 5 µm and 10 µm) for neural tissue engineering applications. In addition, it is also aimed to improve the mechanical properties and stability of the designed biomaterial. The planned groove widths were successfully achieved, and it was observed that the stability was optimally achieved, especially in films exposed to glutaraldehyde vapor. It has also been observed that the addition of PEO to the structure increases the flexibility of the films. It was concluded that it can help guide the progression of cellular neurites and axons along linear lines, within the scope of future potential neural tissue engineering studies of the developed biomaterial. It has also been evaluated that the material can promote regeneration after implantation at a nerve injury site.

Keywords

• Silk fibroin
• Neural tissue engineering
• Micro-grooves
• Electron beam lithography
• Axonal guidance

Nöral Doku Mühendisliği Uygulamalarına Yönelik Mikro-oluklu İpek Fibroin/Polietilen Oksit Film İskelelerin Geliştirilmesi

Öz

Nöral doku mühendisliği alanında, nanoteknolojinin ve biyomalzeme biliminin sunmuş olduğu yeni tekniklerle birlikte, alternatif sinir kılavuz kanalları geliştirmek için yoğun bir şekilde çalışılmaktadır. Fakat doğal ekstraselüler matriksi taklit edebilecek özellikte, intralüminal kanallı yapıda, uygun mikro/nano desenlemelere sahip, nöral hücreleri destekleyecek ve onlara kılavuzluk sağlayabilecek ideal bir nöral iskele henüz tam olarak geliştirilememiştir. Bu çalışmanın amacı; nöral doku mühendisliği uygulamalarına yönelik çeşitli kanal genişliklerine (1 µm, 5 µm ve 10 µm) sahip mikro-oluklu ipek fibroin/polietilen oksit (SF/PEO) film iskelelerin elde edilebilmesi için elektron demeti litografisi tekniğinin kullanımına ilaveten, dizayn edilen biyomalzemenin mekanik özelliğinin ve stabilitesinin geliştirilmesidir. Planlanan oluk genişliklerine başarıyla ulaşılmış olup, özellikle gluteraldehit buharına maruz bırakılan filmlerde stabilitenin optimal olarak sağlandığı gözlenmiştir. Yine yapıya PEO ilavesinin, filmlerin esnekliğini artırdığı görülmüştür. Geliştirilen biyomalzemenin, potansiyel nöral doku mühendisliği çalışmaları kapsamında; hücresel nöritlerin ve aksonların lineer hatlar boyunca ilerlemesine kılavuzluk etmesine yardımcı olabileceği ve bir sinir hasarı bölgesine implantasyonu sonrasında rejenerasyonu destekleyebileceği değerlendirilmiştir.

Anahtar Kelimeler

• İpek fibroin
• Nöral doku mühendisliği
• Mikro-oluklar
• Elektron demeti litografisi
• Aksonal kılavuzluk

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