生細胞試験用３次元磁気テザーの設計・試作と発生力制御

抄録

The present paper discusses a systematic approach to figure out a practical and functional design of sextuple 3D-magnetic tweezer system to perform physical property measurement of biological cell specimens. The authors carried out static and dynamical analyses of the electromagnetic system by using a theoretical model described with closed-loop magnetic circuit using concentrated magnetic charges and finite element analysis. From obtained results, suitable material, optimum tip radius of magnetic poles and number of turns of the driving coil are decided so that maximum magnetic field gradient at the workspace center and allowable anisotropy at outside edge of the workspace can be achieved while desired frequency can also be established. The above design process was applied for drawing out a prototype live-cell experiment system. By using a fabricated prototype, a series of output force measurement experiments were carried out with artificial specimens, silicon oil and grass micro-pipette, the maximum force strength of 140 pN were measured when exertion current of 225A-turns were given. Finally, the prototype system was used to measure the stiffness distribution of yeast cells having two different culturing condition to demonstrate the capability for live-cell experiments.