Magnetic Vortex Nanodiscs Enable Remote Magnetomechanical Neural Stimulation

Area of Science:

• Biophysics
• Materials Science
• Cell Biology

Background:

• Magnetic nanomaterials offer remote control of cellular functions.
• Vortex spin configurations in nanomaterials provide stability and rapid magnetization control.
• Mechanosensory cells respond to physical stimuli, but remote activation methods are limited.

Purpose of the Study:

• To investigate the use of iron oxide nanodiscs with vortex magnetization states as transducers for remote control of mechanosensory cells.
• To demonstrate the magnetomechanical activation of mechanosensitive ion channels using these nanodiscs.
• To explore the potential of magnetic vortex particles in studying mechanoreception and controlling electroactive cells.

Main Methods:

• Colloidal synthesis of magnetite nanodiscs (98-226 nm).
• Magnetic modeling and electron holography to characterize magnetic vortex states.
• Application of nanodiscs to non-mechanosensitive HEK293 cells expressing TRPV4 channels.
• Stimulation using weak, slowly varying magnetic fields (≤28 mT, ≤5 Hz).

Main Results:

• Experimental demonstration of magnetic vortex states in synthesized nanodiscs.
• Successful remote triggering of Ca2+ influx in mechanosensory neurons using magnetic nanodiscs.
• Activation of the TRPV4 channel, confirming magnetomechanical stimulation.
• Cellular response correlated with nanodisc volume and magnetic field parameters.

Conclusions:

• Magnetic vortex nanodiscs function as effective transducers for remote cellular control.
• These particles enable magnetomechanical activation of mechanosensitive ion channels.
• Magnetic vortex particles hold promise for mechanoreception research and controlling electroactive cells with magnetic stimuli.