Static Magnetic Field Increases Survival Rate of Thawed RBCs Frozen in DMSO-Free Solution
The most commonly used cryoprotectant for cells and tissues is dimethyl sulfoxide (DMSO). However, the cytotoxic effect of DMSO is a concern when high concentrations are used. The aim of this study was to assess the cryoprotective effects of static magnetic fields (SMFs) on human red blood cells (RBCs) during cryopreservation. Before the freezing process, RBCs were suspended in media containing 0, 7.5, or 15% DMSO. Then, samples were frozen at −80 °C with a 0.4-T SMF for 24 h. After the cells were thawed, the survival rate, morphology, and mechanical stability of cellular membranes were examined. The results show that SMFs exhibit the largest cryoprotective efficiency when DMSO was not present in the freezing medium. In addition, cell morphology and membrane stability of the frozen-thawed RBCs were not changed after 0.4-T SMF treatment. These results demonstrate that SMFs increase the survival rate of thawed RBCs frozen in a DMSO-free medium. Accordingly, SMF exposure during the freezing process improved the cryopreservation efficiency of RBCs.