کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5530899 | 1549443 | 2017 | 6 صفحه PDF | دانلود رایگان |
This study determined the viscous conditions experienced by cells in the unfrozen freeze concentrated channels between ice crystals in slow cooling protocols. This was examined for both the binary Me2SO-water and the ternary Me2SO-NaCl-water systems.Viscosity increases from 6.9 ± 0.1 mPa s at â14.4 ± 0.3 °C to 958 ± 27 mPa s at â64.3 ± 0.4 °C in the binary system, and up to 55387 ± 1068 mPa s at â75 ± 0.5 °C in the ternary (10% Me2SO, 0.9% NaCl by weight) solution were seen. This increase in viscosity limits molecular diffusion, reducing adsorption onto the crystal plane. These viscosities are significantly lower than observed in glycerol based systems and so cells in freeze concentrated channels cooled to between â60 °C and â75 °C will reside in a thick fluid not a near-solid state as is often assumed.In addition, the viscosities experienced during cooling of various Me2SO based vitrification solutions is determined to below â70 °C, as is the impact which additional solutes exert on viscosity. These data show that additional solutes in a cryopreservation system cause disproportionate increases in viscosity. This in turn impacts diffusion rates and mixing abilities of high concentrations of cryoprotectants, and have applications to understanding the fundamental cooling responses of cells to Me2SO based cryopreservation solutions.
Journal: Cryobiology - Volume 76, June 2017, Pages 92-97