Proceed to passage the cells after culturing them until they reach a cell density of above 80%After discarding the culture medium, wash the cells three times with PBS. Then add one milliliter of trypsin-EDTA solution to the flask and spread it uniformly for full cell contact. Once the cells change from an adherent shape to small, round points, as observed under the microscope at 100X magnification, remove the digestive solution.
Gently tap the flask wall to detach the cells. Add two milliliters of DMEM and repeat rinsing the flask wall 10 times. Gently tap the flask wall and transfer one milliliter of the cell suspension to another glass flask.
Add five milliliters of DMEM to each glass flask. Tap the flask wall gently to distribute the cells evenly. Culture the cells at 37 degrees Celsius with 5%carbon dioxide until the cell density is over 80%