Transformation process of ice crystallized from a glassy dilute trehalose aqueous solution

• Published in: Physical chemistry chemical physics : PCCP Vol. 24; no. 43; pp. 26659 - 26667
• Main Authors: Suzuki, Yoshiharu, Takeya, Satoshi
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 09.11.2022
• Subjects: Aqueous solutions; Cryobiology; Crystal growth; Crystallization; Crystals; Dilution; Ice clouds; Ice formation; Meteorology; Stacking faults; Tissues; Transformation temperature; Trehalose; X ray powder diffraction
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/d2cp02712g

Metastable forms of ice and their crystal growth play an important role in meteorology, cryobiology, and planetary science. However, it is difficult to investigate the effects of solute on the crystal growth of ice in a dilute aqueous solution due to the segregation. Herein, we made a non-segregated glass of dilute trehalose aqueous solution (0.023 mole fraction) and examined the transformation of crystalline ice in the aqueous solution with increasing temperature using powder X-ray diffraction measurements. The ice formed immediately after the crystallization is nano-sized stacking disordered ice (ice Isd) with few stacking faults and has high cubicity. The crystal growth of ice Isd in the trehalose aqueous solution was remarkably slower than those of ice Isd in a glycerol aqueous solution and pure ice Isd. The ice Isd survived up to 230 K which is higher than the transformation temperature from ice Isd to hexagonal ice (ice Ih) of pure water (∼200 K). The existence of trehalose inhibits the crystal growth of ice Isd and, as a result, the ice sublimates easily under vacuum conditions. Moreover, the occurrence of macroscopic segregation at ∼245 K is related to the Isd-to-Ih transformation. These results are important for the improvement of thawing techniques for cryopreserved biological tissues and for the understanding of the mechanism of ice cloud formation in the Earth's atmosphere. Crystal growth of ice Isd occurring after crystallization of a glassy dilute trehalose aqueous solution is slower than that of ice Isd in a dilute glycerol solution and pure ice Isd, and ice Isd in trehalose aqueous solution survives to ∼230 K.