Department of Physics, Capital Normal University, Beijing, 100048, P. R. China.
Department of Physics, Beijing University of Technology, Beijing, 100124, P. R. China.
Small. 2022 Dec;18(52):e2205037. doi: 10.1002/smll.202205037. Epub 2022 Nov 6.
Reducing nanoparticle (NP) dosage for hyperthermia therapy has remained a great challenge. In this work, efficiencies of alternating current (AC) magnetic field and near-infrared (NIR) heating are simultaneously enhanced by Zn and Co co-doping of magnetite NPs. The optimum magnetic anisotropy for maximized loss power under each magnetic field is achieved by tuning the doping concentration. The specific loss power of Zn Co Fe O @SiO NPs reaches 2428 W g under an AC field of 27 kA m at 430 kHz; 12 296 W g under NIR laser irradiation at 808 nm and 2.5 W cm ; and an unprecedented value of 14 724 W g under dual mode. These values far exceed what has been achieved previously in iron oxide NPs. Ex vivo experiments on sacrificial mice show that while the NP dosage is substantially reduced to that used for magnetic resonance imaging, the surface body temperature of the mice reaches 50 °C after exposure to both AC field and laser irradiation under field parameters and laser intensity below safety limits. This nanoplatform is thus promising for multi-modal local hyperthermia therapy.
降低用于热疗的纳米粒子（NP）剂量一直是一个巨大的挑战。在这项工作中，通过磁铁矿 NPs 的锌和钴共掺杂同时提高了交流（AC）磁场和近红外（NIR）加热的效率。通过调整掺杂浓度，可以实现每种磁场下最大损耗功率的最佳磁各向异性。在 430 kHz 时，27 kA m 的交流场下，Zn Co Fe O @SiO NPs 的比损耗功率达到 2428 W g；在 808 nm 和 2.5 W cm 的 NIR 激光照射下，达到 12 296 W g；在双模下，达到了前所未有的 14 724 W g。这些值远远超过了氧化铁 NPs 以前的水平。在牺牲小鼠的离体实验中，尽管 NP 剂量大大降低到磁共振成像所使用的剂量，但在低于安全限制的场参数和激光强度下，将 AC 场和激光照射暴露于小鼠后，其体表温度达到 50°C。因此，这个纳米平台有望用于多模态局部热疗。
