[Polleke]

Someone asked me the following question:
if I know that an OD (600nm) of 1 means I have 1024 cells, then can I calculate how many cells I will have for any random OD value?

I think not, but I am not sure here.
The one asking me this questions things she can simple divide 1024 by 2 for an OD of 0,5.

[Norfeldt]

A quick search on Google gave this http://answers.yahoo.com/question/index?qid=20080811140442AAEEgcJ

You can't just take one measure. You need to make a standard curve. This way you will be sure that you are working inside the space were there is a direct link (proportion) between the OD and count.

[Polleke]

A quick search on Google gave this http://answers.yahoo.com/question/index?qid=20080811140442AAEEgcJ

You can't just take one measure. You need to make a standard curve. This way you will be sure that you are working inside the space were there is a direct link (proportion) between the OD and count.

Yes, this I know, I have this standard curve (or at least someone allready did it for me).

The question is just: if OD 1 means X cells, can I then simply say that OD 0,5 means half the cells? Since its half the OD?

I don care about death cells its.. its just a theoreticall thing here (the cells itself, doesnt matter).

To me it sounds logical that half the OD means half the cells?

But I am getting confused with posts like the one you showed me here.