Objective: The interaction between superparamagnetic iron oxide (SPIO) nanoparticles and mesenchymal stem cells (MSCs) in the presence of pulsed magnetic field (PMF) has become an important area of research in recent years. Methods: A parameter-adjustable pulsed magnetic field was developed based on the principle of insulated gate bipolar translator transistor-controlled discharge of large capacitances. The internalizations of SPIO nanoparticles by MSCs were investigated under the treatment of PMF in both intermittent stimulation mode and continuous stimulation mode. Results: The intensities and frequencies of pulsed magnetic field can be adjustable in the range of 1.9–4.6 mT and 3–5 kHz, respectively. This PMF was safe to the MSCs. However, the uptake of SPIO nanoparticles by MSCs was significantly prohibited under the treatment of kHz-ranged PMF while the 10 Hz PMF enhanced the cellular uptake of nanoparticles. This phenomenon was relative with the magnetic effect of the PMF with different frequency. Conclusion: The PMF can be used to effectively regulate the cellular uptake of SPIO nanoparticles and the mechanism lies in the magnetic effect. Significance: The interaction between SPIO nanoparticles and the MSCs is a fundamental and important issue for nanomedicine and stem cell research. Our results demonstrate that the external magnetic field can be used to regulate their interaction. We believe that this safe, facile, and flexible method will greatly promote the development and clinical translation of regenerative medicine and nanomedicine.

中文翻译：

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KHz脉冲磁场对SPIO纳米颗粒与间充质干细胞相互作用的禁止进入作用

目的：在脉冲磁场（PMF）存在下，超顺磁性氧化铁（SPIO）纳米颗粒与间充质干细胞（MSC）之间的相互作用已成为近年来的一个重要研究领域。方法：基于绝缘栅双极转换器晶体管控制的大电容放电原理，研制了参数可调的脉冲磁场。在间歇刺激模式和连续刺激模式下，在 PMF 处理下研究了 MSCs 对 SPIO 纳米颗粒的内化。结果：脉冲磁场的强度和频率分别在1.9-4.6 mT和3-5 kHz范围内可调。该 PMF 对 MSC 是安全的。然而，在 kHz 范围的 PMF 处理下，MSCs 对 SPIO 纳米颗粒的摄取被显着抑制，而 10 Hz PMF 增强了纳米颗粒的细胞摄取。这种现象与不同频率PMF的磁效应有关。结论：PMF可有效调控SPIO纳米颗粒的细胞摄取，其机制在于磁效应。意义：SPIO 纳米粒子与 MSCs 之间的相互作用是纳米医学和干细胞研究的基本和重要问题。我们的结果表明，外部磁场可用于调节它们的相互作用。我们相信，这种安全、简便、灵活的方法将极大地促进再生医学和纳米医学的发展和临床转化。