冷冻过程中洋葱细胞胞内冰晶的生长行为研究

Study on Intracellular Ice Crystal Growth Behavior of Onion Cells at Different Precooling Rates

细胞胞内冰的形成会导致严重的细胞损伤从而导致低温贮存中的诸多问题。生物组织保存前的预冷过程对胞内冰晶的形成具有重要影响。本文分别采用-1,-5,-10,-20,-50,-80℃/min的降温速率预冷洋葱表皮细胞至-7℃接种冰晶.采用高速摄像仪观察冰晶生长过程,发现了三种模式的胞内冰晶生长行为。模式A:细胞壁结晶后继续在边缘结晶;模式B:细胞壁结晶后,向中心扩散,横贯中心位置;模式C:中心首先结晶,扩散至细胞边缘。最后对三种不同过程的冰晶生长速率及细胞变形度进行了计算分析。

The formation of intracellular ice in the cell could lead to severe cell damage and many problems in cryopreservation. This paper investigates the effects of pre-cooling before ice seeding. The onion epidermal cells were pre-cooled at-1,-,5-10,-20,-50 and-80 ℃/min respectively and the ice is seeded as soon as the cryostage achieved-7 ℃. The high speed camera was used to observe the patterns in the location and formation of intracellular ice crystals and to evaluate the degree of cell deformation. The results showed that an increase in pre-cooling rate influenced the formation pattern of intracellular ice crystals. Mode A： ice crystal first appearing in the cytoderm and spreading to another cytoderm; Mode B： ice crystal spreading toward the center after cytoderm crystallization;Mode C： ice first appearing in the inner cell and spreading to cytoderm. Finally, the growth rate and cell deformability of ice crystals were calculated and analyzed in three different processes.