2021 Volume 67 Issue 1 Pages 15-22
Polyvinyl pyrrolidone (PVP) has been used as a cryoprotectant agent for the cryopreservation of cells. Cell viability of C3H10T1/2 cells after freeze/thaw treatment improved with increasing PVP concentration below 50 wt%. It was revealed that the intracellular brightness became brighter as the PVP concentration increased using optical microscope observation at -70 ºC, indicating that the size of intracellular ice became smaller. The differential scanning calorimetry (DSC) experiment for cell pellets revealed that the amount of intracellular ice was reduced in PVP 50 wt% solution. The cubic-form ice (Ic) was formed in intra-cell, instead of hexagonal-form ice (Ih), as seen using the X-ray diffraction (XRD) experiment for cell pellets extracted from PVP 50 wt% suspension. And the crystallite size of intracellular ice trended to decrease as the PVP concentration increased. Furthermore, it was concluded that the crystallite size of intracellular ice was smaller than that of extracellular ice in the 50 wt% PVP solution. On the other hand, the huge ice was formed through the intra- and extra-cell in 0 wt% (without PVP) solution.
