What is splitting cells and how? - (Mar/15/2006 )

couls some one explain what is meant by splitting cells. What is meant by 1: 5 split, 1: 10 split. 1:7 split etsc..

Splitting cells is the process by which you allow your cells to multiply by separating them (splitting) into different culture flasks. For example, you grow one flask of cells and after three days they are almost fully confluent. They will be eating up plenty of nutrients so you could simply change the medium to kepe them alive. Then take the cells when you need them. Of course you will have no cells left after that so you'd need to grow more from your frozen stocks which will be finite.

If instead you split you cells into 2 or more batches and grow them separately then you increase your number of cells exponentially. One flask becomes, say, 4 flasks each of which could become another four and so on.

What the 1:5, 1:7, 1:10, etc mean is the dilution you perform. So for a 1:5 split you take your cells from a single flask and spin them down into a pellet. Then you add, for example, 5 mL of medium and resuspend the cells. Now you have the choice of preparing up to (though not necessarily) five new flasks into each of which you put 1 mL of the resuspended cells and top up with medium as required. It's the same for 1:10 except you resuspend in 10 mL and put 1 mL in a maxiumum of 10 flasks.

It's the dilution of the cells.

It means that from one flask, you make 5 flasks 1:5, or from 1 mL you make 5 mL of culture.

When adherent cells are confluent, they stop growing. You can scrap them, or trypsinize them, and then you have to dilute them in fresh medium.
non adherent cells needs also to be diluted. There is a limit of concentration you should not reach