Magneto-Induction Heating Properties of Nickel Nanowires under High Frequency Magnetic Field

本論文研究的主要目的在探討以電化學沈積法製備成的鎳奈米線在交變磁場下之發熱特性。近年來，奈米線已應用於生醫方面，例如:生物細胞分離、生物感測器、熱炙治療等生醫用途。而在熱炙治療方面，許多研究使用具有超順磁特性的磁性奈米粒子作為發熱材料進行腫瘤治療，而本研究以自製鎳奈米線作發熱測試，並分為三個部分進行探討: 第一部分為鎳奈米線的製備，本研究以電化學沉積法進行製成，其電鍍時間分別為15分鐘及30分鐘，可得直徑為200 nm、長度為10 μm及15 μm的鎳奈米線，再以氫氧化鈉去除陽極氧化鋁濾膜 ( AAO )，並將其乾燥成粉末狀以作發熱量測。 第二部分為利用100 kHz的射頻磁場進行重量為1 mg的鎳奈米線粉末之發熱測試，在一系列不同交變磁場的量測下，可觀察到其發熱功率在交變磁場強度為12 Oe時有大幅上升的現象，且發現小於此磁場強度時，15 μm的鎳奈米線升溫較10 μm鎳的奈米線高，但大於12 Oe時，10 μm鎳奈米線的發熱反而較佳。進一步將其排列成平行及垂直於交變磁場方向再進行量測，可發現平行磁場排列時有最佳的發熱功率。 第三部分為量測不同重量的鎳奈米線之發熱情形，同樣將其分別排列後再進行量測，並將結果與重量為1 mg時的升溫與SAR作比較，得知鎳奈米線數量越多時，其升溫越高，但SAR卻變化不大。 由本研究之鎳奈米線的發熱特性分析，可知在交變磁場強度為12 – 14 Oe時已有高溫發熱效果，且處於生物體安全範圍 ( H∙f <6.09×〖10〗^6 Oe/sec ) 內，可作為未來在熱炙治療方面的應用與參考。The purpose of this thesis is to study the heating properties of nickel nanowires made of electrochemical deposition. The nanowires have been utilized for biomedical applications in recent years, such as cell separation, biosensor, hyperthermia therapy and so on. The superparamagnetic nanoparticles have been used in most of hyperthermia therapy studies for clinical cancer treatment. In this study, we use nickel nanowires for the heating experiment and discuss them in three parts: The first part is about the fabrication of Ni nanowires. In this study, Ni nanowires were fabricated by electrochemical deposition. Time of fabrication for depositing is 15 minutes and 30 minutes respectively. We obtain the Ni nanowires with two different lengths of 10 μm and 15 μm, which diameter is 200 nm. After deposition, anodic aluminum oxide (AAO) was removed by NaOH and Ni nanowires were dried into powders. The second part is about the heating characteristics of 1mg, Ni nanowire powders under 3 - 14 Oe altering magnetic field of 100 kHz. After the heating experiments, we could observe the heating power rose obviously under the 12 Oe altering magnetic field. Besides, the rising temperature of 15 μm NWs was larger than 10 μm NWs when the amplitude of field was smaller than 12 Oe, but 10 μm NWs had larger heating power when the amplitude of field was larger than 12 Oe. In addition, we set up Ni NWs lined up in parallel and perpendicular to the altering magnetic field respectively. We observe Ni NWs have the optimal heating property when they were parallel to the altering magnetic field. The third part is about the heating properties of different weights of Ni-NW powders. After the heating experiment, the rising temperature and SAR compare with the results of 1mg Ni NWs. We discover that the rising temperature is much higher when we increase the weight of Ni-NW powders, but the variation of SAR is small. In this study, we know that Ni NWs have large heating effect under 12 - 14 Oe altering magnetic field, which in the safe range of the organisms under the radio-frequency (RF) magnetic field ( H∙f