Investigation of Electromagnetic Resonance Rewarming Enhanced by Magnetic Nanoparticles for Cryopreservation.

The lack of effective rewarming technique restricted the successful cryopreservation of organ or large tissues by vitrification. The conversion of electromagnetic (EM) energy into heat provides a possible solution for the rewarming process for the cryopreservation. In this work, an EM resonance rewarming system was set up with dynamic feedback control and power feeding optimization. In addition, we take advantage of magnetic nanoparticles (MNPs) to absorb magnetic field energy to further enhance the energy conversion efficiency. We achieved over 200 C min-1 rewarming rate for tens of mL cryopreserved samples. Besides, we also investigated the effect of nanoparticle size and concentration based on thermal properties analyzing the contribution of nanoparticles and utilization of field energy. The closed system reduced the possible concomitant side effects when increasing nanoparticles or raising EM source power. With the remarkably low dosage of nanoparticles (0.1 mg mL-1 Fe) compared to other MNP based rewarming applications, this study opens a door for new approaches to explore novel techniques for the tissue and organ preservation.