Hello everybody.

I´m isolating DNA and RNA from cell culture samples using the clasical Trizol method and it would be great to include RNase treatment in the DNA extraction protocol.

I´m wondering which is the best moment to performance RNase treatment in this protocol. Maybe it´s better to do it after the DNA washing step but I guess that if I do it, it will be necessary to make a PCI extraction+EtOH precipitation and it could be a really time consuming task...

Thank you for your advice, kind regards.

Briefly:

a. DNA Precipitation

• After centrifuging take Phenol phase and interphase + 0.3 ml ethanol, spin

b. DNA Wash (DNA Wash Solution: 0.1 M trisodium citrate in 10% ethanol)

• 1 ml DNA Wash Solution, 2 x 30 min RT, spin
• 1.5ml 75% ethanol, spin

c. DNA Solubilization

8 mM NaOH, then adjust pH