本研究是以樹枝狀高分子為核心，樹枝狀高分子為一新發展的高分子，其特色在於化學鍵從中心的核由內向外發散，形成樹枝狀的分枝，利用其高度分枝的結構，在表面官能基上，可經由適當改質而接上不同的分子作多功能的運用，而將之應用在生醫材料方面。
本實驗以PEG作為核心，採發散式合成法向外產生分枝的OH表面官能基，合成出一至三代的樹枝狀高分子，並在高分子表面接枝上經螯合穩定之造影活性釓元素MRI顯影劑、具癌症主動標的功能的葉酸、及抗癌藥物MTX。實驗結果顯示，由樹枝狀高分子所攜帶多個顯影劑，能大幅提高每單位分子造影劑的訊號強度，可有效運用於醫學造影上。而接上葉酸後，由於其癌組織辨識的效果，可增加載體被癌症細胞攝取的機會，因此在醫學上，未來可結合醫學造影以及癌症治療，利用此多功能藥物載體，一方面將藥物有效送至癌組織，一方面利用MRI隨時偵測治療情形。且材料經由細胞毒性測試，證實其具有生物相容性，因此在生醫材料的利用上，有其發展的可行性。

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