Tensorial representation of ionophoresis effects by MRI

The goal of this study is to make active or passive electrical characteristics of biological systems visible by magnetic resonance imaging (MRI). As a starting investigation, we visualized a precise flow effected by ionophoresis. We used CuSO4 doped water (25 mM) electrolytes in an ionophoresis cell composed of a pair of horizontal copper electrodes. An evaluation of ion drift, we made by MR diffusion tensor imaging method. The impressed voltage was 0.0-0.5 V, and the current density at that time increased monotonously was 0.00-1.06 mA/cm2. With increasing current density, higher values of drift diffusion coefficient (DDC) induced by the electric field were observed. The diffusion tensor ellipsoid in current density of 1.06 mA/cm2 was successfully visualized as the effects of ion drift induced by the electric field. By applying this method to biological systems, it has a possibility to make functional electrical characteristics visible. (author)