Abstract
In cryopreservation of cells, the bell-shaped cell survival curve with an optimal cooling rate is understood on the basis of two-factor hypothesis, i.e. extracellular- and intracellular-freezing injuries. The intracellular freezing injury was already modeled successfully and mathematically based on intracellular ice formation. In this study, a mathematical model with reaction kinetic formulation was newly proposed to describe the extracellular freezing injury. A parameter study of model constants was performed to evaluate the cell survival rate as a function cooling rate. The model constants were also determined by inverse problem analysis based on the experiment with human erythrocytes. The experiment and prediction by the model were compared on the cell survival curve. The result shows that the extracellular freezing-induced cell death is successfully described by the reaction kinetic model.
