about extract RNA from spleen - (May/21/2002 )
We have tried several agents(such as TRizol, TRipure ) to extract total RNA from mouse spleen.But we found our samples are always contaminated with DNA by PCR assay. And the OD260/OD280 is below 1.7 . Our manipulation is completely the same as that required in the protocol. What's the possible reason? Thank you very much!
As far as I know, just about every RNA kit out there will have some DNA contamination in the RNA, so it may not be your sample handling prior to isolating the RNA. I would say that you could DNase treat the samples and then heat treat to kill DNase activity. That is what we do when we use the Purescript kit.
AronD is correct. From personal experience it is very frustrating to get a full length genomic DNA clone when trying to get the cDNA from an RT experiment. DNase digestion is probably the best way to avoid this.