Magnetomechanical Force-Driven Cell Permeabilization via Pulsed Magnetic Field and Magnetic Nanoparticles.

As a non-contact physical intervention technique, pulsed magnetic field (PMF) has been shown to regulate cell membrane permeability. However, the underlying mechanism remains unclear, and their permeabilization efficiency is relatively low. Building on the advantages of magneto-mechanical regulation with magnetic nanoparticles, this study proposes combining PMF with magnetic nanoparticles. By leveraging magneto-mechanical force (MMF) as the central mechanism, the aim is to enhance cell permeabilization rate through optimization of the applied force magnitude. First, a theoretical analysis of the forces acting on magnetic nanoparticles was performed to guide particle parameter selection. Next, the effects of PMF alone and its combination with magnetic nanoparticles on cell membrane permeability were examined through in vitro experiments. Finally, fluorescence probes were used to investigate the biochemical mechanisms underlying cell permeabilization induced by both treatments. The permeabilization experiment results showed that the combined treatment significantly enhanced cell permeabilization. Compared to PMF treatment alone, the half-maximal effective dose decreased by 27.85%, and the rate of change in permeabilization rate increased by 49.7%. Fluorescence staining further revealed that, unlike the biochemical pathways activated by PMF treatment alone, the combined treatment caused multiple disruptions in cytoskeletal microfilaments, confirming that it induced cell permeabilization through a physical mechanism involving mechanical stress. This study leveraged the MMF generated by magnetic nanoparticles under PMF to regulate cell membrane permeability, providing a novel approach for precise control of cell membrane permeability based on physical parameters.