Design of microstructure for stimulating mechanical torque to cells

In this study, we proposed the design for microstructure which can apply bending or torsion stimulus to cell using an external magnetic field. First, we defined “ideal bending stimulus” and “ideal torsion stimulus” for cell on a microstructure. In order to apply ideal bending or torsion stimulus to cells, the thickness of the microstructure of cell-culturing region is important. We designed and microfabricated the microstructure which consists of a thin silicon beam as cell-culturing region and a ferromagnetic material, nickel film for magneto-active structure. Then, fabricated microstructures actuated by external magnetic field and deformation of the microstructures was measured. From the results of the measurements, we calculated radius of curvature and angle of torsion respectively and we confirmed the platform almost actuated in theory. Our design of the platform can contribute to applying new kinds of mechanical stimuli to cultured cells.