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为了理论预测细胞最优化低温保存方案,提出了冷冻过程细胞内变组分、变温三元溶液系统的冰晶成核及其生长模型.数值模拟结果表明:(1)较高降温速率下,胞内冰体积份额随初始甘油浓度的增加呈线性减小.(2)实现溶液玻璃化的临界降温速率随初始甘油浓度的增加而减小:没有甘油存在时,1.25×10 13℃/min;初始甘油浓度为7.4 mol·L-1时,为20 ℃/min;当初始甘油浓度大于7.4 mol·L-1时,所有降温速率均能达到玻璃化保存.本研究通过获得初始甘油浓度和降温速率二维平面图中可实现细胞内玻璃化的区域,从而提供了一种细胞最优化低温保存方案的理论预测方法.“,”To theoretically predict the optimal protocol for cryopreservation of biological cells,a model for intracellular ice formation and its growth in a ternary solution of both temperature and concentration varying was developed.The modified water transport equation developed by us in 2006,ice nucleation,and the diffusion-limited ice growth theory were coupled to constitute this model.Typical cryopreservation processes for mouse oocytes being frozen in glycerol-water-NaCl ternary solutions were simulated.The finally crystallized volume fraction,together with the finally normalized intracellular water volume,as a function of both initial glycerol concentration and cooling rate was predicted by the model.Simulation results indicated that,(I) the normalized intracellular water volume decreased with the increase of initial glycerol concentration.(ii) the crystallized volume fraction decreased linearly with the increase of initial glycerol concentration at higher cooling rates,and first increased and then decreased with the increase of the cooling rate: (a) the critical cooling rate,I.e.,the minimum cooling rate necessary to vitrify intracellular solution,decreased from 1.25×10 13 ℃/min to 20 ℃/min along with the increase of the concentration of glycerol from 0 to 7.4 mol·L-1,and (b) for initial glycerol concentration higher than 7.4 mol·L-1,any cooling rate could vitrify intracellular solution.This model provides a theoretical method for prediction of the optimal protocol for cryopreservation of biological cells by seeking a combined region from the two dimensional figure of initial glycerol concentration versus cooling rate.