Devitrification and Recrystallization of Aqueous Glycerol and PEG-600 Solutions with Nanoparticles

Abstract

Nanoparticles in solution offer unique electrical, mechanical and thermal properties due to their physical presence and interaction with the state of dispersion. This work aimed to study the effects of hydroxyapatite (HA) nanoparticles on the behavior of devitrification and recrystallization of glycerol (60% w/w) and PEG-600 (50% w/w) solutions during warming. HA nanoparticles of different sizes (20nm40nm60nm) and contents (0.1%0.5%,w/w) were incorporated into solutions, and were observed under a cryomicroscope. Experimental results showed that the morphologies of glycerol and PEG-600 solutions are dendritic and spheric respectively. The ice fraction of glycerol solution containing 0.1% HA with the size of 60nm decreased to 2/5 of that of solution without nanoparticles. The ice fractions of PEG-600 solutions with and without nanoparticles increased significantly between-64 °C and-54 °C, and the ice fraction of PEG-600 solution without nanoparticles increased by 92% within the temperature range. The findings have significant implications for biomaterial cryopreservation, food manufacturing, and cryosurgery.