| 摘要: | 褐藻酸鈉(Sodium alginate, ALG)是一個帶有負電的生物可降解高分子，在同一個環境中會與同帶負電的DNA去競爭正電高分子。在文獻中曾提到將褐藻酸鈉/DNA/聚乙烯亞胺(Polyethyleneimine, PEI)三種成分複合而成奈米粒子，藉由競爭來降低DNA與聚乙烯亞胺間的相互關係，並因此提高了基因轉染的效果。由於疊層組裝(Layer-by-Layer)系統對於細胞轉染表現還有增進的空間，所以在本篇研究中，我們想要利用褐藻酸鈉、DNA與聚乙烯亞胺三成分進行疊層組裝疊層組裝，形成(DNA/PEI/ALG/PEI)的模型，探討其物化性質並觀察是否也同樣能提升對細胞的轉染表現。從接觸角與紅外光譜來看我們知道三成分確實有吸附於材料表面。接著，在紫外光度計與石英微量天平的量測觀察中發現隨著褐藻酸鈉層濃度的提升(0.004, 0.02, 0.1, 0.5 g/l)，對於疊層組裝中DNA的吸附與釋放效果也會跟著提高，相較於由DNA與聚乙烯亞胺製備的疊層組裝在DNA吸附量來說可以提升到兩倍以上並且DNA釋放量提高50%左右，並且更深入去由大小與複合程度探討多層膜釋放出來粒子型態。結果顯示，在褐藻酸鈉濃度為0.1 g/l製備的疊層組裝能得到最佳的細胞轉染表現。Sodium alginate(ALG) is a biodegradable polyelectrolyte with negative charges, which may compete the positive polyelectrolyte with anionic DNA. Therefore, some reports indicated that alginate can interact with DNA/polycation and form a triple component complex. This particle is able to enhance the gene transfectrion efficiency due to electrostatic neutralization of the complex. Due to this property, we want to complex the three component with layer-by-layer(LbL) to enhance the transfection ability. So, in this study, we use different alginate concentration(0.004, 0.02, 0.1, 0.5 g/l) create the (DNA/PEI/ALG/PEI)4 LbL model and investigate the properties of DNA changes during the multilayer system measuring by ATR-FTIR, contact angle, quartz crystal microbalance (QCM), UV-vis, DLS and eletrophoresis gel. We observe there is two-fold DNA release at the 0.1g/l alginate assembly condition and the DNA adsorption increase with increasing alginate concentration. Also, the particle size which release from the multilayer increase too. At least, we use the multilayer to transfect the NIH/3T3 cells. Observing the transfction efficiency at 0.1g/l of (DNA/PEI/ALG/PEI)4 multilayer enhanced up to three times compare to (DNA/PEI)4 . |
