中文摘要：

以纳米Fe304粒子为原料，通过空气氧化法，制备出了具有不同磁性能的球形和立方形纳米γ-Fe2O3粒子，研究了纳米γ-Fe2O3粒子的磁性能及其在交变磁场下的发热性能，对其在定向集热治疗肿瘤中的应用前景进行了评价。纳米γ-Fe2O3粒子的比饱和磁化强度为44.18～69．84A·m^2／kg，矫顽力为（13～17）×79，6A/m。纳米γ-Fe2O3粒子含量为20mg／ml时，在外加交变磁场作用下15min后，纳米γ-Fe2O3粒子生理盐水悬浮液的温度为38．6～54．4℃，随着纳米γ-Fe2O3粒子比饱和磁化强度的增加，其在交变磁场中所达到的最高温度增大，有3种纳米γ-Fe2O3粒子达到了医学上定向集热治疗肿瘤用热籽的发热要求，纳米γ-Fe2O3粒子是很有应用前景的医用纳米材料。

英文摘要：

The γ-Fe2O3 nanoparticles with different magnetic properties were prepared by oxidation of Fe304 nanoparticles in the air. The inductive heating properties of the γ-Fe2O3 nanoparticles in an alternating current （AC） magnetic field were investigated for local hyperthermia. The potential of the γ-Fe2O3 nanoparticles was evaluated for localized hyperthermia treatment of cancers. The saturation magnetization Ms and coercivity Hc of γ-Fe2O3 nanoparticles were 44.18-69.84 A·m^2/kg and （13-17）×79.6 A/m respectively. Exposed in the AC magnetic field for 15 min, the temperatures of physiological saline suspension containing γ-Fe2O3 nanoparticles with concentration of 20 mg/ml were 38.6-54.4℃. The inductive heating property of γ-Fe2O3 nanoparticles in AC magnetic field increased with the increasing of Ms. The γ-Fe2O3 nanoparticles would be useful as good thermoseeds for localized hyperthermia treatment of cancers.