Drzewiński Andrzej, Marć Maciej, Wolak Wiktor W, Dudek Mirosław R
Institute of Physics, University of Zielona Góra, ul. Szafrana 4a, 65-069 Zielona Góra, Poland.
Nanomaterials (Basel). 2022 Sep 3;12(17):3064. doi: 10.3390/nano12173064.
Stable aqueous suspension of magnetic nanoparticles is essential for effective magnetic hyperthermia and other applications of magnetic heating in an alternating magnetic field. However, the alternating magnetic field causes strong agglomeration of magnetic nanoparticles, and this can lead to undesirable phenomena that deteriorate the bulk magnetic properties of the material. It has been shown how this magnetic field influences the distribution of magnetic agglomerates in the suspension. When investigating the influence of the sonication treatment on magnetic colloids, it turned out that the hydrodynamic diameter as a function of sonication time appeared to have a power-law character. The effect of magnetic colloid ageing on magnetic heating was discussed as well. It was shown how properly applied ultrasonic treatment could significantly improve the stability of the colloid of magnetic nanoparticles, ultimately leading to an increase in heating efficiency. The optimal sonication time for the preparation of the magnetic suspension turned out to be time-limited, and increasing it did not improve the stability of the colloid. The obtained results are important for the development of new materials where magnetic colloids are used and in biomedical applications.
磁性纳米颗粒的稳定水悬浮液对于有效的磁热疗以及在交变磁场中的其他磁热应用至关重要。然而，交变磁场会导致磁性纳米颗粒强烈团聚，这可能会引发不良现象，使材料的整体磁性能恶化。已经展示了这种磁场如何影响悬浮液中磁性团聚体的分布。在研究超声处理对磁性胶体的影响时，结果表明，流体动力学直径作为超声处理时间的函数呈现出幂律特性。还讨论了磁性胶体老化对磁热的影响。结果表明，适当应用超声处理可以显著提高磁性纳米颗粒胶体的稳定性，最终导致加热效率提高。制备磁性悬浮液的最佳超声处理时间是有限的，延长时间并不能提高胶体的稳定性。所获得的结果对于使用磁性胶体的新材料开发以及生物医学应用具有重要意义。
