question for the measurement of OD600 - (Nov/03/2006 )

Hi, all,

Would someone can explain me how to measure the OD600 of my bacterium? I mean, do I need dilute it (let's say 100 times) when I measured like DNA measurement or I do not have to dilute?

Best regards,

Kuo-Tung

no, u do not need to dilute it if u have enough of it. just put into a cuvette the proper amount and measure the OD

Thanks.

But if I dilute it 100 times, whether the value is the same as not dilution?
Maybe I can have a try...

I would dilute 10-fold to read an overnight culture (high OD). If I'm looking at an exponential culture, I wouldn't dilute. A 100 fold dilution will likely get the OD too low for the spectrophotometer to read it accurately.

if you are in the linear phase 0.2 - around 0.7 you don't have to dilute. Above 0.8 I would consider doing a 10x dilution. As you start leaving the linear part of the graph.

The machine that I use is old, and doesn't read accurately below OD = 0.2, I am not sure about modern machines which may be better.