As this occurs, all solutes are excluded from the ice and therefore become more highly concentrated in spaces between the ice crystals. They squash cells, disrupt their internal structure, puncture or tear their membranes, and rip them apart from each other and their extra-cellular structure. Second, naturally occurring chemicals such as sodium and potassium salts become more highly concentrated as they are expelled from among the freezing water molecules. These higher concentrations become toxic. Vitrified solutions do not contain localized toxic concentrations and will not cause mechanical damage.
Vitrified solutions have the same composition as liquid solutions.
Since they are uniform, they will not contain localized toxic concentrations and no mechanical damage will occur. Glycerol can enable vitrification if it is sufficiently concentrated. Bearing this in mind, Cryobiologists have tried to use lower concentrations of glycerol while maximizing their effectiveness by other means. One method is to cool the tissue rapidly, allowing less time for toxic reactions that occur more slowly at lower temperatures. Fast cooling also allows less time for ice to form.