Need advice on counting low cell numbers - (Jun/20/2008 )
Hello - I am currently doing an experiment that requires seeding 5000-10000 cells in 24-well plates, and then counting these cells at specific time points. My problem is that isolating (trypsinising) and properly counting the cells is difficult. What volume do you recommend I count these cells at? I have to use a hemacytometer because we do not have an automated cell counter available. I have been counting with a total volume of 0.5ml, but the numbers I get vary greatly (sometimes it is 2, sometimes it is 8). Is there a better method, or should I Just use a lower volume to count with?
You don't count individual cells in this kind of expts.
Assys that measure mitochondrial dehydrogenase activity will give you a measure of number of live cells in each well. If you must have number of cells, you can first create a dilution curve using this assay ranging from lowest to highest cell counts that you expect.
Links for one such assay can be found here: