兩性共聚合物與不同型態之氧化鐵之磁熱效應表現

The Effect of Self-Assembled Morphology of Amphiphilic Copolymers and Shape of Iron Oxide Nanoparticles on Hyperthermia Performance

黃元春(Yuan-Chun Huang)

指導教授 ： 王麗芳

高雄醫學大學/生命科學院/醫藥暨應用化學系碩士班/碩士(2017年)

摘要

本實驗中，由兩性團鏈式高分子(PCL)60-SS-(PMAA)60共聚物，Poly（ε-caprolactone）-SS-Poly（methacrylic acid），簡稱PSP。依據不同的化學組成方法，將PSP製備成兩種不同形態的高分子奈米粒子，微胞（micelle，PSPm）與囊胞（polymersome，PSPps）。同時，製備兩種不同形狀的氧化鐵奈米粒子，柱狀氧化鐵（IONRs）與斜截八面體氧化鐵（IONPs），分別導入奈米微 / 囊胞中，製成四種不同組合的磁性奈米粒子，分別為：奈米微胞包覆柱狀氧化鐵（PSPm-IONRs），奈米微胞包覆斜截八面體氧化鐵（PSPm-IONPs），奈米囊胞包覆柱狀氧化鐵（PSPps-IONRs），奈米囊胞包覆斜截八面體氧化鐵（PSPps-IONPs）。
接著，利用氧化鐵奈米粒子的磁熱效應，於交流磁場下進行高溫熱治療，與核磁共振顯影診斷成像，兼具治療與診斷的雙功能應用。使用穿透式電子顯微鏡（TEM）、X光繞射儀（XRD）、超導量子干涉儀（SQUID）、核磁共振影像儀（MRI）、交流磁場高溫熱療機（AMF Hyperthermia）等儀器，觀察此四種組合之間的差異。再經由細胞存活率分析（MTT Assay），流式細胞儀（Flow Cytometry），及共軛聚焦顯微鏡（CLSM）等確認材料在生物體外的細胞毒性及材料進入細胞內的追蹤觀察。
最後，經由上述實驗結果確認此四種磁性奈米粒子中，具最佳磁熱療效為PSPps-IONPs。於CRL-5802腫瘤細胞中餵入材料濃度為200 ppm的磁性奈米粒子PSPps-IONPs，經由交流磁場高溫熱療儀，於頻率為37.6 kHz下，進行高溫熱治療15分鐘，其細胞致死率可達50%以上。推測可能原因為，氧化鐵奈米粒子的大小與形狀影響其磁熱效果或是PSP不同形態影響CRL-5802腫瘤細胞的胞飲能力；之後更進一步將表面修飾鍵結親水性的螢光試劑，使用流式細胞儀及共軛聚焦顯微鏡探討原因，證明PSP包覆氧化鐵為具潛力發展為多功能診斷及治療平台。

關鍵字

微胞 ； 囊胞 ； 氧化鐵 ； 超順磁性質 ； 磁滯熱療 ； 診斷 ； 治療

並列摘要

Our group has developed two nanoparticles with different morphologies including polymersomes and micelles based on (PCL)60-SS-(PMAA)60 copolymers （Poly（ε-caprolactone）-SS-Poly（methacrylic acid），PSP）. We synthesized two different shapes of iron oxide (truncated octahedral and rod-like) nanoparticles and introduced them to PSP-formed polymersomes as well as micelles, to produce four combinations: truncated octahedral iron oxide nanopolymersome (PSPps-IONPs), rod-shape iron oxide nanopolymersome (PSPps-IONRs), truncated octahedral iron oxide nanomicelle (PSPm-IONPs) and rod-shape iron oxide nanomicelle (PSPm-IONRs), respectively. These four samples sustained a superparamagnetic property, which can be directed by applying an exterior magnetic field for specifically targeting to a tumor site, similarly to the surface modification with a targeting ligand. In addition, these samples can be utilized in the alternative magnetic field for hyperthermia therapy, and in nuclear magnetic resonance imaging (MRI) for diagnosis, integrating both of the therapeutic and diagnostic dual-applications. At the current stage, we have characterized the samples with transmission electron microscopic (TEM), X-ray diffractometer (XRD), superconducting quantum interference device (SQUID), magnetic resonance imaging (MRI), alternative magnetic field (AMF) for hyperthermia. We have performed many in vitro experiments such as a MTT assay to observe the cell viability, a flow cytometric study to evaluate the cellular uptake ability, and a confocal laser scanning microscope (CLSM) to trace the localization of nanoparticles. Basing on the experimental results, we found that the PSPps-IONPs had the highest magnetic efficiency in hyperthermia performance. The cell viability of CRL-5802 cells was < 50% upon exposure to 200 ppm PSPps-IONPs and treatment with AMF hyperthermia device using 37.6 kHz for 15 minutes. The truncated octahedral iron oxide nanoparticles had the higher saturated magnetism than the rod-like iron oxide nanoparticles. This fact resulted in the higher r2 value of which combination, the higher r2 value the higher performance in MRI diagnosis. Taken together, our study results demonstrate that PSP-encapsulated iron oxide nanoparticles are potential nanomedicines for theranostic applications.

並列關鍵字

micelle ； polymersome ； iron oxide ； superparamagnetic ； AMF hyperthermia ； diagnosis ； therapy

參考文獻

1. 馬振基, 奈米材料科技原理與應用. 化學 2012.

2. 李玉寶, 奈米生醫材料─奈米研究應用系列. 化學 2006.

3. Na, H. B.; Palui, G.; Rosenberg, J. T.; Ji, X.; Grant, S. C.; Mattoussi, H., Multidentate Catechol-Based Polyethylene Glycol Oligomers Provide Enhanced Stability and Biocompatibility to Iron Oxide Nanoparticles. ACS Nano 2012, 6 (1), 389-399.

4. Mahmoudi, M.; Sant, S.; Wang, B.; Laurent, S.; Sen, T., Superparamagnetic iron oxide nanoparticles (SPIONs): Development, surface modification and applications in chemotherapy. Advanced Drug Delivery Reviews 2011, 63 (1–2), 24-46.

5. Laurent, S.; Forge, D.; Port, M.; Roch, A.; Robic, C.; Vander Elst, L.; Muller, R. N., Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications. Chemical Reviews 2008, 108 (6), 2064-2110.