摘要
为了研究冷冻过程中胞内溶液均相成核温度下降值与平衡凝固点下降值的关系,提出了一种求解变组元系统成核温度的方法,并联合细胞脱水方程,进行了数值求解.研究发现,甘油-氯化钠-水三元系统的均相成核温度下降与平衡凝固点下降存在如下的线性关系:"Th=1.17"Tm,表明水溶液均相成核温度与溶质有关.
In order to study the homogeneous nucleation temperature of intracellular solution during cooling, an iteration method has been presented to calculate nucleation temperature of system with changeable concentrations. Glycerol was chosen for a cryoprotective agent （CPA） during cooling of mouse oocytes. The equilibrium melting points of intracellular solutions were calculated using an empirical equation determined by the phase diagram of glycerol- sodium chloride-water temary system. The widely used cell dehydration equation was numerically solved and the concentrations of intracellular solutions as a function of time were calculated. The assumption that the homogeneous nucleation temperature depression was directly proporlianal to the equilibrium melting point depression has been used. The homogeneous nucleation temperatures of intracellular solutions as a function of concentrations were then calculated using the new proposed method coupling with the equilibrium melting points and the concentrations of intracellular solutions. It was found that for glycerol-sodium chloride-water temary system, depression of the homogeneous nucleation temperature and depression of the equilibrium melting point followed the relation： △Th = 1.17△Tm . The result proved that the assumption was reasonable and showed that homogeneous nucleation temperatures of aqueous solutions depended on solutes. This research can provide convincing data to support the further study of intracellular ice formation and growth during cooling.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2008年第1期74-78,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(50475100)资助项目
关键词
细胞脱水
平衡凝固点
均相成核温度
低温保护剂
Cell dehydration
Equilibrium melting point
Homogeneous nucleation temperature
Cryoprotective agent
