Adherent cells in the mitotic phase detach, can be collected by shaking.

1. Grow cells in a large flask to subconfluent (mid-log phase).

2. Shake-off mitotic cells by gentle shaking or tapping of the flask or by gently washing with the warm medium.

3. Transfer the medium containing mitotic cells to a sterile tube, store on ice.

4. Add fresh pre-warmed medium to the flask and return it to the incubator.

5. Repeat step 2-4 every 10-30 minutes until enough cells have been collected.