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Please help me to understand- cell counting - (Apr/15/2010 )

I am a beginner so please help me to understand following:

I centifuge my cells and dissolve the pellet in 5 ml media.

In 5ml cell suspension I have 250 mil cells/ml
In this 5 ml cell suspension I counted the cells and I have 1,8 mil cells/ml

I want 1 mil/ml and want to make 10 ml cell suspension

So I have 250 mil cells in 1ml
10 ml *10^6 cells= 10 mil cells ( in 10 ml I have 10 mil cells)

10 mil cells/ 250 mil cells = 0,04 ml= 40 ul. So I take 40 ul from my 5 ml cell suspesnion, but I need 10 ml in total volume so to the 40 ul cells ( I took from my 5ml cell suspension) I will add 9,96 ml media.

Is this calcultation right or this one below:

In 5ml cell suspension I have: 5ml *250 mil cells/ml= 1250 mil cells

1250 mil/10 mil = 8 ul I will take from the 5 ml cell suspension and I will add around 9,92 ml media

Thank you!


you have 250mil cells per ml.

and you need 1 mil cells per ml, so you need to dilute it 250 times.

This means you add 249 ml to 1 ml of your start solution.
and there you go. You have 250 ml of a 1mil cells per ml solution.

If this 249ml is too much you can start with 0.5ml of the start solution and add 249/2 ml or you take 0.1ml and add 24.9ml....

It all depends on whats the easiest way for you to work.

What you are doing, I do not get it. If you take 40Ál from the 250mil cells per ml then you have indeed 10mil cells ; but you have 10mil cells in your 40Ál ... so if you add new volume to that 40Ál you will dilute your cells and not have 10mil cells per ml. Or do you just need 10mil cells?