利用聚乙二醇和葉酸接枝於石墨包覆鐵磁性奈米粒子做癌症之熱治療

Abstract

雖然氧化鐵在現今的研究中，為生物醫學最普遍應用的磁性奈米粒子，不過因為石墨包鐵(GEI)奈米磁性粒子有強大的磁性，所以為有潛力的新材料。為了增加粒子對癌症細胞貼附的專一性和效率，聚乙二醇(PEG)和葉酸(FA)被接枝在石墨包鐵奈米粒子上面。 FTIR、UV和TEM影像的結果，可以顯現合成的PEG-FA分子可以成功地接枝在GEI奈米粒子的表面上。而對於已經接枝上的奈米粒子(GEI-PEG-FA)可以在水中分散的優異行為，在Seztasier的試驗可以被證實。而在體外(in vitro)對GEI-PEG-FA奈米粒子所做的毒性測試以LDH和WST-1測試，由LDH 測試可以證實GEI-PEG-FA奈米粒子的毒性是相當低的，並且由WST-1測試可以證實GEI-PEG-FA奈米粒子對細胞增生有些微的影響。除此之外，藉由鐵含量的測定，可以知道細胞表面有許多葉酸接受器的HeLa細胞能夠攝入比GEI奈米粒子更多的GEI-PEG-FA奈米粒子。而由穿透式電子顯微鏡的照片所見，HeLa細胞可以藉由內吞作用，攝入GEI-PEG-FA奈米粒子。

Although iron oxide is the most popular magnetic nanoparticle for biomedical applications in the present studies, graphite-encapsulated iron (GEI) magnetic nanoparticle is a novel and potential material owing to its powerful magnetic properties. In order to enhance the specific and efficient targeting into cancer cells, polyethylene glycol (PEG) and folic acid (FA) were immobilized on the GEI nanoparticles. FTIR, UV and TEM images results indicated that the synthesized PEG-FA complexes were successfully conjugated on the surface of GEI nanoparticles. The in vitro experiments for cytotoxicity of GEI-PEG-FA magnetic nanoparticles were performed by LDH and WST-1. The relative low cytotoxicity of GEI-PEG-FA nanoparticles was examined by LDH, and the WST-1 showed cell proliferation was slightly affected by GEI-PEG-FA nanoparticles. By iron determination, HeLa cells with overexpressed folate receptors on cell membranes could uptake more developed GEI-PEG-FA nanoparticles than GEI nanoparticles. The HeLa cells uptake GEI-PEG-FA nanoparticles via endocytosis can be seen from TEM images.