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bioRxiv · 10.1101/2021.08.16.455233

Magnetic Nanoprobes for Spatio-Mechanical Manipulation in Single Cells

Dr. Novoselova, I. P.·Neusch, A.·Brand, J.-S.·Otten, M.·Safari, M. R.·Bartels, N.·Prof. Karg, M.·Prof. Farle, M.·PD Wiedwald, U.·Prof. Monzel, C.
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Abstract

Magnetic nanoparticles (MNPs) are widely known as valuable agents for biomedical applications. Yet, for their successful application within cells they need to fulfill a variety of demands such as monodispersity, biocompatibility or sufficient magnetic response. Given these prerequisites, MNPs may be used for remote, non-invasive manipulation, where their spatial redistribution or force response in a magnetic field provides a fine-tunable stimulus to a cell. Here, we investigate the properties of two different MNPs and their suitability for spatio-mechanical manipulations: semisynthetic magnetoferritin nanoparticles and fully synthetic nanoflower-shaped iron-oxide nanoparticles. Next to characterizing their structure, surface potential and magnetic response, we monitor the MNP performance in a living cell environment using fluorescence microscopy and confirm their biocompatibility. We then demonstrate their capability to spatially redistribute and to respond to magnetic force gradients inside a cell. Our remote manipulation assays present these tailored magnetic materials as suitable agents for applications in magnetogenetics, biomedicine or nanomaterial research.

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Dr. Novoselova, I. P., Neusch, A., Brand, J.-S., Otten, M., Safari, M. R., Bartels, N., Prof. Karg, M., Prof. Farle, M., PD Wiedwald, U., Prof. Monzel, C.. 2021-08-16. Magnetic Nanoprobes for Spatio-Mechanical Manipulation in Single Cells. https://doi.org/10.1101/2021.08.16.455233

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