A molecular dynamics study of cryoprotective agent - Water-sodium chloride ternary solutions

Molecular dynamics simulation method has been used to study the characteristics of cryoprotective agent (CPA) solutions with glycerol as a CPA at normal and subzero temperatures. Radial distribution functions have been calculated. The geometrical criterion has been used to analyze hydrogen bonding network and dynamics. It has been found that the mean number of hydrogen bonds per oxygen atom decreases as glycerol concentration increases. The mean number of hydrogen bonds per hydrogen atom show little dependence on solute concentration. The mean number of hydrogen bonds per water molecule decreases as solute concentration increases. The relaxation time and the hydrogen bonding lifetime show tendencies of increasing as solute concentration increases. The lifetimes of hydrogen bonds between water molecules are smaller than those between glycerol and water molecules. The hydration numbers of sodium cation and chlorine anion and water self-diffusion coefficients have also been reported. The results have been used to analyze the protection of cryoprotective agent.