Effect of applied electric field on the formation and structure of ice in biomaterials during freezing

The extra or intracellular ice crystal during the freezing of biomaterials is lethal to cells. It is an important topic in cryobiology how to control, reduce, or even eliminate the ice formation. The purpose of this study is to testify an assumption that electric field could significantly influence ice formation and induce the structure of microcrystal or glassy ice in some samples at a relative slow cooling rate. Physiological saline (0.9wt.%) as the sample, was applied a uniform electric field with the strength of 0~10³V/m. The formation and structure of ice were analyzed by thermodynamic course and dielectric spectroscopy, which indicated that under electric field saltine ice increased and pure ice decreased significantly. When E=1×10³ V/m, supercooling and relative dielectric constant increased conspicuously. Furthermore, the related theories of crystallography and dielectric physics were used to explain the experimental results. This preliminary results show that a certain electric field might be such a promising approach to control the formation and structure of ice during the slow cooling process of biomaterials.