The effect of pH value and temperature of pyrrolidone on PVP aqueous solution plays a role in cell seed preservation. Proper operation and suitable freezing conditions can reduce the change or loss of cell characteristics. Uncross-linked PVP solution has no special thixotropy, unless it is thixotropic at high concentration and shows a very short relaxation time. Experience in cell freezing: Choosing the right freezing tool is the best way. Cell freezing is a technology that stores cells in a low temperature environment, reduces cell metabolism, and achieves long-term storage. (Pyrrolidone) In most cell lines, the thickening performance of PVP is closely related to its relative molecular mass. Under given concentration conditions, the larger the relative molecular mass, the greater its viscosity. Cells will continue to accumulate and change with aging and evolution, causing "culture drift" of phenotype and genotype. Correct and successful freezing plays an important role in the long-term application of cells.
During the freezing process, therefore, correct culture and gentle cell collection, before freezing, cells should maintain the best growth state (in the logarithmic or exponential phase). Ideally, the culture medium should be replaced 24h before harvesting. It is recommended to check the culture for microbial contaminants, especially mycoplasma, to ensure that the cells are not contaminated. During the cell collection process, the experimental operation should be as gentle as possible to avoid cell damage. (Pyrrolidone) Appropriate cryoprotectant. At present, the commonly used technology for cell freezing is liquid nitrogen cryopreservation, which mainly uses slow freezing method with appropriate amount of protective agent to freeze cells and reduce damage to cells during the freezing process. If cells are directly frozen without protective agent, the water inside and outside the cells will quickly form ice crystals, causing a series of adverse reactions.
Polyvinyl pyrrolidone, ethylene glycol, methanol and methylacetamide are all cryoprotectants. Dimethyl sulfoxide (DMSO) and glycerol are common in cell cryopreservation. These two substances have small molecular weight, high solubility, and can easily penetrate cells. They can lower the freezing point and increase the permeability of cell membranes to water. The key lies in the cell nature. (Pyrrolidone) DMSO usually has a concentration of 5-10% (v/v), and the optimal concentration varies with different cell lines. The final concentration of glycerol in the freezing medium is 5-15%. Similarly, the optimal concentration depends on the cell line. In order to increase the survival rate of cells that are difficult to preserve, you can choose to increase the serum concentration in the preservation solution during cryopreservation. If you want to freeze cells faster and more steadily, cell freezing solution would be a good choice. No preparation is required. Just add an appropriate amount of freezing solution to the cells. The operation is simple and you can have cells with high viability.
