There are two ways to adapt cells to serum-free medium (SFM): 1. Direct adaptation to the method—Transfer cells directly from serum-added medium to serum-free medium. 2. Continuous adaptation or sequential isolation method-the cells are switched from serum-added medium to serum-free medium in several steps. Compared with the direct adaptation method, the continuous adaptation method is gentler for the cells. In order to adapt the cells to serum-free medium, the key is that the cell culture should meet the following conditions: 1. In the middle of logarithmic growth 2. Survival rate is greater than 90% 3. During the adaptation period, inoculate with a higher initial cell inoculation volume. The routine adaptation steps are listed below. The initial cell seeding volume, cell yield and culture cycle are good starting points for continuous optimization. Direct adaptation Some types of cells can be adapted directly from serum-containing medium to serum-free medium. For direct adaptation, the cell seeding volume should be in the range of 2.5 x 105 -3.5 x 105 cells / ml. When the cell density reaches 1 x 106-3 x 106 cells / ml, subculture the cells. After 4 to 7 days of culture, when the cell density reaches 2 x 106 -4 x 106 cells / ml, the cells have completely adapted to the serum-free medium. When the cell density reaches 1 x 106 -3 x 106 cells / ml and the survival rate is 90%, the stored cells adapted to serum-free medium should be subcultured in serum-free medium every 3 to 5 days. Automatic Curtain Pole,Automatic Curtains Alexa,Automatic Curtains Price Jilin Province Yuaoda Trading Co., Ltd , https://www.yuaodacn.com