Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke St, Cambridge, UK.
Ultrasound Med Biol. 2011 Jan;37(1):169-75. doi: 10.1016/j.ultrasmedbio.2010.09.007. Epub 2010 Nov 16.
Magnetite (Fe(3)O(4)) nanoparticle agglomerates have been shown to enhance the degree of inertial cavitation induced by high-intensity focused ultrasound (HIFU). To investigate the effect of these particles on the destruction of tumor spheroids using HIFU, HeLa spheroids were insonated in the presence and absence of magnetite nanoparticle agglomerates. The HIFU transducer was operated with a frequency of 1.1 MHz, pulse repetition frequency of 1.67 kHz, 5% and 50% duty cycles and peak negative focal pressure of 7.2 MPa for 10 s. The significant increase in the HIFU-induced inertial cavitation caused by the presence of magnetite particles at 50% duty cycle was sufficient to cause cell lysis and disintegrate the whole spheroid (p ≤ 0.001). This suggests that magnetite nanoparticle agglomerates can enhance the efficacy of HIFU in tumor ablation and other related therapies.
磁铁矿（Fe3O4）纳米颗粒聚集体已被证明可以增强高强度聚焦超声（HIFU）诱导的惯性空化程度。为了研究这些颗粒对 HIFU 破坏肿瘤球体的影响，在存在和不存在磁铁矿纳米颗粒聚集体的情况下对 HeLa 球体进行了声处理。HIFU 换能器以 1.1 MHz 的频率、1.67 kHz 的脉冲重复频率、5%和 50%的占空比以及 7.2 MPa 的峰值负压工作 10 s。在 50%占空比下，由于存在磁铁矿颗粒，HIFU 诱导的惯性空化显著增加，足以导致细胞裂解并使整个球体解体（p≤0.001）。这表明磁铁矿纳米颗粒聚集体可以增强 HIFU 在肿瘤消融和其他相关治疗中的疗效。
