近年來,奈米磁性粒子在過高熱(Hyperthermia)癌症療法已經逐漸受到重視。結合高飽和磁化率與表面活性基團的奈米磁性粒子，強化了奈米磁性粒子針對癌細胞或癌組織進行標靶治療的功能，目前奈米氧化鐵粒子已有許多在過高熱療法摧毀癌細胞的研究與改良。然而，奈米氧化鐵粒子容易聚集的特性導致磁化率以及溶液中的分散性降低而沉澱，而高分散性的奈米磁性粒子-碳粒子複合物則可以改善粒子聚集的問題，並同時具備低生物毒性，大大增加了在生醫方面應用的可能性。此外，單壁奈米碳角(SWNHs)預期在藥物傳遞上有高發展性，因為單壁奈米碳角的表面改質在藥物傳遞應用中也是一重要的研究方向，因此，結合單壁奈米碳角(SWNHs)與奈米氧化鐵的複合物可具有同時針對癌細胞進行標靶性過高熱療法與藥物傳遞化學療法的優點。
此篇研究探討20奈米以下粒徑氧化鐵(Fe3O4)的合成，並透過水熱法(Hydrothermal process)在奈米氧化鐵粒子表面包覆碳粒子形成複合物(Fe3O4@C)，並由碳粒子表面的親水基團(-COOH基與–NH2基)進行複合物表面改質，達到粒子高分散性效果。此外，單壁奈米碳角(SWNHs)與奈米氧化鐵複合物(SWNH/Fe3O4)的合成使用兩種合成方式進行 : 利用羧基與胺基形成化學鍵的化學合成法；與利用羧基與鐵離子間的電荷引力達到材料複合目的。
由穿透式電子顯微鏡(TEM)影像可得知，包覆碳粒子的奈米氧化鐵(Fe3O4@C)雖然大幅提升粒子在溶液中的分散性，卻依然無法完全克服粒子聚集的狀況，以致奈米氧化鐵(Fe3O4@C)與單壁奈米碳角(SWNHs)的合成上雖具化學鍵結，卻有不均勻分布的現象。相對的，使用羧基與鐵離子間的電荷引力的合成法，雖無具有化學鍵結，則沒有不均勻的現象。

Magnetic nanoparticles for hyperthermic treatment of cancers have gained significant attention in recent years. In particular, iron oxide nanoparticles are being actively investigated to achieve highly efficient destruction of carcinogenic cells through magnetic hyperthermia treatments. However, magnetic nanoparticles, Fe3O4, tend to aggregate to form the thermodynamically favored bulk metal, which results in the loss of magnetism and dispersibility of naked magnetic nanoparticles. The highly dispersible magnetic carbon nanostructures may exhibit favorable chemical reactivity and minimal cytotoxicity. This offers promising opportunities in biomedical applications.
Therefore, in this research, Fe3O4 magnetite nanoparticles with diameter under 20 nm were synthesized by using co-precipitate method. Moreover, the surface of Fe3O4 magnetite nanoparticles was coated with carbon dots (Fe3O4@C) by hydrothermal process which led to the appearance of the hydrophilic functional group (-COOH and –NH2) on magnetite surface. Additionally, acid-treated SWNH/magnetite hybrid nanoparticles were prepared by different methods which were the amidation of Fe3O4@C with acid-treated SWNHs and the direct synthesis of Fe3O4 on acid-treated SWNHs via ionic interaction.
TEM images of SWNHs/Fe3O4@C demonstrated that some SWNHs were attached by the aggregate of Fe3O4@C particles. However, TEM images of SWNHs/Fe3O4 showed that SWNHs were attached to clusters of magnetite particles which completely and homogeneously surrounded SWNHs. These results reveal a possibility to improve the magnetite dispersion by using functionalized carbon nanohorns.

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