Fig. 6

Mechanism of different types of zirconium-based metal and organic frame-based nanoregulators (MOF NPs) inhibiting ice crystal growth [145, 146]. A Schematic illustration of the solvothermal synthesis of MOF-801 NPs. B The formation process of MOF-808 NPs. C MOF-801 NPs as a cryoprotectant for preventing cell injury caused by ice crystal growth during cell freezing and thawing (left). Ice recrystallization inhibition effect of MOF-801 NPs by controlling the NPs size and introducing ice-binding amino acids that affect the micro curvature on the ice surface. The anchored water molecules allow the MOF-801 NPs to adsorb well to certain ice planes (right). D MOF-808 NPs form hydrogen bonds with water molecules to inhibit the growth of ice crystals. E The equilibrium of adhesion and separation between MOF-808 NPs and the ice surface makes it a “catalyst”, which accelerates the exchange of water molecules at the interface between ice and free water, thus promoting the melting of ice crystals