Institute of Biothermal Science & Technology, University of Shanghai for Science and Technology, Shanghai 200093, China.
Shanghai Co-innovation Center for Energy Therapy of Tumors, Shanghai 200093, China.
Langmuir. 2023 Aug 8;39(31):11048-11062. doi: 10.1021/acs.langmuir.3c01364. Epub 2023 Jul 27.
Rapid and uniform rewarming is critical to cryopreservation. Current rapid rewarming methods require complex physical field application devices (such as lasers or radio frequencies) and the addition of nanoparticles as heating media. These complex devices and nanoparticles limit the promotion of the rapid rewarming method and pose potential biosafety concerns. In this work, a joule heating-based rapid electric heating chip (EHC) was designed for cryopreservation. Uniform and rapid rewarming of biological samples in different volumes can be achieved through simple operations. EHC loaded with 0.28 mL of CPA solution can achieve a rewarming rate of 3.2 × 10 °C/min (2.8 mL with 2.3 × 10 °C/min), approximately 2 orders of magnitude greater than the rewarming rates observed with an equal capacity straw when combined with laser nanowarming or magnetic induction heating. In addition, the degree of supercooling can be significantly reduced without manual nucleation during the cooling of the EHC. Subsequently, the results of cryopreservation validation of cells and spheroids showed that the cell viability and spheroid structural integrity were significantly improved after cryopreservation. The viability of human lung adenocarcinoma (A549) cells postcryopreservation was 97.2%, which was significantly higher than 93% in the cryogenic vials (CV) group. Similar results were seen in human mesenchymal stem cells (MSCs), with 93.18% cell survival in the EHC group, significantly higher than 86.83% in the CV group, and cells in the EHC group were also significantly better than those in the CV group for further apoptosis and necrosis assays. This work provides an efficient rewarming protocol for the cryopreservation of biological samples, significantly improving the quantity and quality of cells and spheroids postcryopreservation.
快速且均匀的复温对于冷冻保存至关重要。目前的快速复温方法需要复杂的物理场应用设备（如激光或射频）以及添加纳米颗粒作为加热介质。这些复杂的设备和纳米颗粒限制了快速复温方法的推广，并带来了潜在的生物安全问题。在这项工作中，设计了一种基于焦耳加热的快速电加热芯片（EHC）用于冷冻保存。通过简单的操作，可以实现不同体积的生物样品的均匀和快速复温。EHC 加载 0.28 毫升的 CPA 溶液可以实现 3.2×10°C/min 的复温速率（2.8 毫升时为 2.3×10°C/min），与激光纳米加热或磁感应加热相结合时，与同等容量的 straw 相比，复温速率提高了约 2 个数量级。此外，在 EHC 冷却过程中无需手动成核即可显著降低过冷度。随后，细胞和球体的冷冻保存验证结果表明，冷冻保存后细胞活力和球体结构完整性显著提高。冷冻保存后人类肺腺癌细胞（A549）的存活率为 97.2%，明显高于低温瓶（CV）组的 93%。人骨髓间充质干细胞（MSCs）也出现了类似的结果，EHC 组的细胞存活率为 93.18%，明显高于 CV 组的 86.83%，EHC 组的细胞在进一步的凋亡和坏死检测中也明显优于 CV 组。这项工作为生物样品的冷冻保存提供了一种高效的复温方案，显著提高了冷冻保存后细胞和球体的数量和质量。
