Biomedical Engineering Reference
In-Depth Information
Cell
Adding nanoparticles targeting
receptors on cell membrane
Applying external
magnetic field
Twisting
Vertical pulling
Horizontal pulling
Figure 7.8
An illustration depicts three main techniques in
magnetic stimulation of cells: twisting, vertical pulling, and
horizontal pulling.
membrane. To create a twisting effect, ferromagnetic particles (particles carry a
magnetic moment) are used and the applied magnetic field is applied at an angle
to the magnetization vector of the particles. Since this twisting technique offers a
localized force without cell deformation, it is an excellent tool to study the function
of the receptors and the adhesive protein molecules in mechanotransduction.
7.3.3
Limitation of Using Magnetic Nanoparticles for Cell Stimulation
Since magnetic nanoparticles are biocompatible, internalization of nanoparticles
is inevitable. Once internalized, the nanoparticles are no longer attached to the ion
channels on the cell membrane, travel through the cytoplasm toward the nucleus,
and stimulation is not possible. This internalization process takes place in a matter
of hours [49]. Moreover, the speed of internalization generally increases as the
particle size decreases [50-52].
One possible solution is to target the receptors inside the cell. This requires a
fast internalization process, usually aided by using lipids, and instant attachment
of the nanoparticles to the internal receptors. Unfortunately, there is no successful
research using such a complicated system.
