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Problem on negative control in Xgal - Question, suggestion (Oct/24/2006 )

After ligation i have blue white colonies on my samples and also in my negative control. Incubation is 20 hours. My positive control has lawn colonies only. Im thinking that i may have confused the neg and pos controls during the plating in Amp plates with X-gal. I know i need to repeat the experiments, but i want to hear from the kind hearted experts here first. I welcome all advices.

Thanks smile.gif


Hi there!

When you're doubting yourself about maybe you pippeted the wrong thing in A instead of B or such things, in my experience it is best to trow away everything and do it again...