Design of a linear magneto-mechanical bio-actuator for cell-alignment in tissue engineering

Abstract:
This paper aims to design and construct a bio-actuator to stimulate cell growth remotely through a magneto-mechanical approach. With this approach, the cell culture can be isolated from the outside, achieving a more sterile environment than traditional mechanical approaches. To accomplish this, the cellular scaffold, hydrogel, is embedded with Fe3O4 powder to become magnetic. Two electromagnets with cylindrical iron cores generate an alternating magnetic gradient field in the cell culture to dynamically pull the magnetic gel (ferrogel). With a specific three-phased structure, the ferrogel can be stretched uniaxially. FEM Simulation and analytical calculation have been carried out to create gradient fields and minimize temperature input for cell culture. The excitation currents of the electromagnet are regulated with PI control in the microcontroller due to the coil-heating. Finally, a preliminary cellular experiment shows that smooth muscle cells can normally grow and differentiate in the ferrogel and achieve a perpendicular alignment to the axial direction.