A promising direction in designing the efficient poly-component cryoprotective media may be the use of novel synthetic compounds, e.g. the recrystallization inhibitors, possessing the features of natural antifreeze proteins, that can help to reduce ice recrystallization at the heating stage. In particular, polyvinyl alcohol (PVA) is one of these compounds.
The strategic direction of the laboratory's activity for next 4–5 year is a novel approach to design the modern efficient cryopreservative media or human erythrocyte freezing, which are composed of substances with amphiphilic and hydrophilic properties (e.g. 1,2-PD and glycerol) and including the substances controlling the crystal formation, e.g. polyvinyl alcohol with MW of 9 and 31 kDa.
The phenomenon of cluster crystallization of cryoprotective solutions near their vitrification temperatures has been experimentally revealed and theoretically elucidated. It has been shown that at such low temperatures, the ice microcrystals can be formed through a homogeneous mechanism without breaking the hydrogen bonds between the water molecules and cryoprotective substance. The state diagrams containing the area of existence of the resulting cluster phase, have been plotted. A possible contribution of cluster crystallization into the mechanisms of damage to biological objects during cryopreservation in cryoprotectant aqueous solutions are investigated.