中文摘要

為了解決奈米碳管毒性及藥物攜帶能力，本研究將陰離子型雙親媒性團聯共聚物鍵結於奈米碳管表面，此雙團練共聚物由甘素(Heparin)與聚乙醇乳酸(polyglycolic acid)所構成，本研究設計三種奈米碳管載體:M-COOH(氧化奈米碳管)、M-Hep(肝素分子鍵結於奈米碳管表面)以及M-PGA(Poly(heparin-co-glycolic acid) 鍵結於奈米碳管表面)，經電子顯微鏡觀察，M-PGA載體中，雙團聯共聚物會在奈米碳管表面形成高分子微胞，並有助於提升原本奈米碳管之藥物攜帶量，且經高分子鍵結於奈米碳管表面後破壞了原本奈米碳管鍵長且增加奈米碳管之直徑，且材料毒性測試中顯示M-PGA生物毒性最低，當我們利用M-PGA為載體攜帶速溶艾黴素(Doxorubicin)且與人子宮頸癌細胞共培養，實驗結果顯示，載體攜帶藥物毒性高於單純藥物使用，此結果顯示M-PGA在藥物輸送上有較高效率，並由共軛交顯微鏡觀察到，M-PGA是直接累積於細胞核中，且藥物能有效從載體釋放釋放，本研究建立一高效率藥物攜帶性載體且能有效輸送DNA-TOXINs至細胞核提升治療效率。

Abstract
(Drug Loaded and Encapsulating Efficiency)

In this study, three kinds of hybrid nanotubes, i.e., oxidized multi-wall carbon nanotubes (M-COOH), heparin-conjugated multi-wall carbon nanotubes (M-Hep), and tri-block hybridizedpolyglycolic acid (PGA)–heparin multi-wall carbon nanotubes (M-PGA), were synthesized for improved biocompatibility and drug-loading capacity. Hydrophilic heparin substituents on multi-wall carbon nanotubes (MWCNTs) can improve their biocompatibility, while the addition of PGAcan improve theirdrug-loading capacity. In M-PGA system, the amphiphilic copolymers (PGA-Hep) formed micelles on the side wall of carbon nanotubes (CNTs), as confirmed by electron microscopy observations. The encapsulation ability of the hydrophobic molecule in each of the three carriers was also investigated by using the pyrene as model of hydrophobic drug; M-PGA encapsulates the hydrophobic molecule with a high efficiency. M-Hep is bulkier than M-COOH, which makes it more difficult to attach drugs to M-Hep than to M-COOH due to steric interactions; as a result, M-Hep has a lower drug-loading capacity. M-PGA is more efficient than M-COOH and M-Hep encapsulating drugs since it can loaded drug through hydrophobic and π-π stacking interaction.
Keywords: Carbon nanotube, Drug carrier, Amphiphilic copolymer, Nucleus targeting, Heparin, Polyglycolic acid

Abstract
(Nucleus Targeting)

Doxorubicin (DOX) is currently used in cancer chemotherapy to treat many tumors and presents enhanced delivery, decreased toxicity and higher treatment efficacy when being part of nanoscale delivery systems. Thus, CNTs as one of drug nano carrier have been developed to assist delivery of DOX. Functionalized CNTs, such as M-COOH, M-Heparin, and M-PGA, has ability to encapsulate the DOX in different percentage of loading capacity. We also investigated the toxicity and the drug release of M-COOH, M-Heparin, and M-PGA. From confocal result, it can be obtained that M-PGA acted as carrier has efficiently delivered and released DOX in nucleus. In addition, from toxicity result, M-PGA its self were presented as the most biocompatible material in comparison with M-COOH and M-Heparin. However, When DOX loaded M-PGA, the toxicity become increase, attributing successfully nucleus targeting strategy and drug are able to release from M-PGA.

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