DNA、RNA和蛋白质在血液样本的稳定性同样受到反复冻融的影响。有研究显示，从-70℃冻存的血液样本复融一次，会降低25%的DNA产量 [1] ，但是不会改变血浆或者血清mRNA的浓度 [2] 。

相反，Kopreski等研究发现冻融血清导致mRNA的快速降解，反复冻融三次，进行RNA扩增后几乎无法检测到 [3] 。Baumann等研究人员发现融解一次冻存的血清样本的蛋白质组学图谱具有最好的重现性，反复冻融多次显著改变冻存血清和血浆样本的蛋白质组学表型图谱 [4] 。

多次冻融血浆样本，血管内皮生长因子（Vascular Endothelial Growth Factor，VEGF）水平显著降低 [5,6] 。Hsieh等研究发现，在冰上重复解冻存储于-80℃的血浆和血清样本10次，并没有明显改变低分子量蛋白分子的蛋白组学 [7] 。这些研究显示，不同的研究对象和冻融参数（如冻融的时长、冻融次数）对研究的影响各不相同。

因此，通常情况下，我们尽量避免反复冻融血液样本。根据实验的需求，可以将收集的血液样本分成多份或者直接提取DNA等相对稳定的分子进行存储。我们既提供经济实惠的无编码的常规冻存管，还提供某些需要进行样品战略存储的三码合一冻存管，客户可以根据实验需求进行选择。相关产品信息可以咨询当地授权经销商或者直接联系我们。

参考文献

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