Vitrification is an ultra-rapid cryopreservation technique that cools oocytes or embryos at a rate greater than 10,000°C per minute, preventing ice crystal formation by transitioning the cell directly into a glassy (vitreous) state. At that cooling rate, water molecules in the cell do not have time to form the crystalline ice structures that cause mechanical damage to cell membranes and organelles. The result is a sample that enters storage in a stable amorphous solid state, with minimal physical disruption to the cell.
Slow-cooling cryopreservation uses a controlled rate freezer to lower the sample temperature at a programmed rate — typically between -1°C and -3°C per minute. At this rate, water exits the cell osmotically before freezing, reducing but not eliminating intracellular ice formation. Slow-cooling remains appropriate for sperm banking in andrology units and for certain cell lines.
For oocyte and embryo cryopreservation in IVF laboratories, vitrification has become the standard approach because post-warming survival rates are significantly higher than slow-cooling for these cell types. Cryolab supplies CBS High Security vitrification kits and the CBS DigitCool controlled rate freezer range for laboratories using both approaches. Contact Cryolab for product and protocol guidance.
