The determination of ideal protective agent concentration requires comprehensive consideration of cell type, freezing rate, and thawing conditions. Usually, a two-step method is used to add protective agents: slowly add at room temperature to avoid osmotic pressure shock, and then achieve equilibrium at low temperatures. The removal of protective agents after thawing is also crucial, and gradient dilution is needed to prevent cell swelling. However, the concentration and duration of use of these protective agents need to be precisely controlled, otherwise toxic effects may occur.The traditional method of using liquid nitrogen for freezing can achieve low temperatures, but it cannot precisely control the cooling process. This' extensive 'freezing method carries significant risks. What modern biopharmaceuticals need is a "precise" cooling system that can accurately control the temperature at every step.Key breakthrough in technological implementation: Taking Grant CRFT liquid nitrogen free program cooling instrument as an example, modern refrigeration equipment has achieved precise control through multiple technological innovations:

• Accurate temperature control system:Electronic temperature control replaces liquid nitrogen, achieving a temperature control accuracy of ± 0.5 ° C and supporting linear cooling control of 0.1-10 ° C/min

• Full process data tracking:Real time recording of the temperature curve of the entire freezing process to ensure the traceability and repeatability of the experimental process

• Multi scenario application support:Suitable for various sample types such as organoids, cell lines, stem cells, etc., supporting the full process requirements from basic research to GMP production

• Intelligent programming:Multiple freezing programs can be preset to meet the optimal freezing needs of different cell types