PLLA 引導組織再生支架的製備

Abstract

本研究使用PLLA和PLGA兩種高分子作為實驗的主要材料， PLLA和PLGA是具有良好生物相容性以及生物可分解性的人工合成高分子，實驗中，利用此兩種高分子製備具有組織整合性和細胞阻擋性的引導組織再生支架，希望能夠應用來治療牙周病所導致的齒槽骨缺損問題。 我們使用熱誘導式相分離法(TIPS)來製備適合細胞生長的多孔支架，經過電子顯微鏡觀察，支架的孔洞具有不對稱性，而從支架截面觀察到支架具有良好的孔洞連通性。在製程上，我們調控高分子濃度和製程溫度來控制支架的孔洞大小，並且探討支架孔洞大小隨著高分子濃度和製程溫度改變的趨勢。根據此趨勢試驗出合適的條件來製備具有組織整合性和細胞阻擋性的支架孔洞(接觸骨頭細胞的孔洞約100μm，接觸牙齦纖維母細胞的孔洞約需5μm左右)，並且發展出二種方式，將分別具有約100μm孔洞的支架和具有約5μm孔洞的支架黏合成引導組織再生支架。細胞阻擋性測試結果顯示：本研究所製備的引導組織再生支架，的確可以有效地阻擋牙齦纖維母細胞通過。

Poly(L-lactic acid) and poly glycolic acid were used to fabricate porous biodegradable scaffolds suitable for bone regeneration, based on the thermally induced phase separation(TIPS) technique. Polymer concentration and quenching temperature are major parameters involved in our TIPS process. We examined the two parameters in detail to produce porous structures suitable for tissue integration and cell occlusivity. The conditions which fulfill our purpose are as follows: The 3% PLLA solution quenched at -20℃ resulting scaffolds with pore size around 100μm and the 6% PLLA solution quenched at -20℃ resulting scaffolds with pore size around 5μm. The 100μm pores can provide space for bone cells to attach and grow and the 5μm pores are managed to separate soft tissue. Moreover, we developed two methods to glue together the scaffolds with 100μm and 5μm pores, and GTR scaffolds were thus prepared. Finally, the cell occlusivity of the prepared GTR scaffold was tested, and the results showed that the scaffold can prevent the penetration of gingival fibroblasts for at least 4 weeks.