Manipulation of cellular orientation and migration by internalized magnetic particles

The quick response of magnetic nanoparticles (MNPs) to an external field provides a unique way for cellular manipulation in a remote and non-contact mode. In this work, we demonstrate the modulation of cellular behaviors including orientation and migration based on internalized Fe3O4 nanoparticles in a particle-concentration dependent manner. After being treated with MNPs at low concentrations (e. g. 0.277 mu g mL (-)1), the internalized particles separately distributed around the nuclei, and somewhat influenced the orientation of the cells along the direction of the external magnetic field. In contrast, when the concentration of MNPs was high enough (e. g. 2.770 mu g mL (-1)), the particles formed clusters within the cells and moved towards the edges of the cell in the direction of the magnetic field, leading to an obvious morphological change and subsequently a directed migration of the cells. This result shows a facile way to manipulate cell behaviors with excellent biocompatibility and its potential application in the biomedical field such as in tissue engineering.