Development of new biocompatible magnetic materials and the application to hyperthermia of cancer

新型生物相容性磁性材料的开发及其在癌症热疗中的应用

基本信息

批准号：
08559007
负责人：
MATSUI Masaaki
金额：
$ 4.54万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1998
项目状态：
已结题

项目摘要

We have investigated the magnetic materials which is used for hyperthermia of cancer under the high frequency alternating magnetic field (H) . The hysteresis loss heat generation and Curie temperature (Tc) have been measured for several materials. The biocompatibility of materials has been taken into consideration. The summary is listed as follows.1) Magnetic properties and the heat generation of Mg-Fe-M-0 (M=Ti, Si, K, Ca) oxides was investigated. In the Mg_<1+x>Fe_<2-2x>Ti_x0_4 system, the Curie temperature (Tc) decreased with increasing x, from 635K for x=0.0 to 200K for x=0.5. The heat generation Q=16W/g for x=0.0 at H=100 Oe decreased to 3W/g for x=0.35 at room temperature. We found that the Ti substitution is best for hyperthermia.2) Ultra fine particles of Fe_3O_4 were made by the chemical method. The particles with diameter less than 2Onm showed the lower Tc than bulk (850K) . Tc decreased with decreasing the diameter and 660K for 5nm was achieved as minimum Tc. It is concluded that the decrease of diameter is an appropriate method to decrease the Tc.3) Ultra fine particles of Co wera investigated. It was difficult to obtain the Co particles with a diameter less than 2Onm. Tc of the particles with 2Onm in diameter was almost same to bulk value. Co particles are not appropriate for hyperthermia.4) Artificial metallic superlattices including Fe atomic layers were made. The minimum of Tc for alpha-Fe was 350K at 1.3 monolayer (ML) and that for gamma-Fe was 300K at 0.8 ML of Fe. It was concluded that such superlattices with ultra thin atomic layers has the appropriate Tc but could not be used for hyperthermia, because the quantity of production by one process is very small.

我们研究了在高频交变磁场（H）下用于癌症热疗的磁性材料。已测量了多种材料的磁滞损耗发热和居里温度 (Tc)。考虑了材料的生物相容性。主要内容如下：1)研究了Mg-Fe-M-0(M=Ti、Si、K、Ca)氧化物的磁性能和发热情况。在Mg_<1+x>Fe_<2-2x>Ti_x0_4体系中，居里温度（Tc）随着x的增加而降低，从x=0.0时的635K降低到x=0.5时的200K。室温下，H=100 Oe 时 x=0.0 时的发热 Q=16W/g 降至 3W/g（x=0.35 时）。我们发现Ti替代物最适合热疗。2)采用化学法制备了超细Fe_3O_4颗粒。直径小于20nm的颗粒表现出比块状颗粒(850K)更低的Tc。 Tc 随着直径的减小而降低，5nm 的最小 Tc 达到 660K。结论是减小直径是降低Tc的合适方法。3)对Co超细颗粒进行了研究。很难获得直径小于20nm的Co颗粒。直径为20nm的颗粒的Tc与本体值几乎相同。 Co颗粒不适合热疗。4)制备了包括Fe原子层的人造金属超晶格。 α-Fe 的最低 Tc 在 1.3 单层 (ML) 时为 350K，而 γ-Fe 在 0.8 ML Fe 时的最低 Tc 为 300K。结论是，这种具有超薄原子层的超晶格具有合适的Tc，但不能用于热疗，因为一种工艺的生产量非常小。