Cell passaging

Adherent cultures should be passaged when they are in the log phase before they reach confluence, otherwise, it takes them longer to recover when reseeded. Normally, you can detect that visually by estimating the percentage of confluence as the amount of free space between cells. Usually, the normal range to perform the cell passage is 70-90%. seventy to ninety percent. It is also important to passage your cells according to a programmed schedule to ensure a reproducible behavior that allows you to monitor their health status. Deviations from the growth patterns usually indicate that the culture is unhealthy or a component of your culture system is not functioning properly. Therefore, it is strongly recommended to keep a detailed cell culture log of the cell growth.

Disassociation techniques

The first step in subculturing adherent cells is to detach them from the surface of the culture vessel. You can do that using enzymatic or mechanical procedures, as you can see in the table below.

Procedure Dissociation agent
Shake-off Shaking or rocking of culture vessel, or vigorous pipetting
Scraping Cell scraper
Enzymatic dissociation Trypsin, Trypsin+collagenase, Dispase, TrypLETM

Referred from: