Small yield of RNA after on column DNAs digestion , Why - (Feb/21/2014 )
I extracted RNA from duck tissue and it was really high quantity 2000 ng/µl by nanodrop. After that I repeated the extraction with on coulmn DNAse digestion and the quantity dramatically dropped down to 120 ng/µl
What is cause, is the Nanodrop measure the RNA and the DNA together ?
Yes, it fails to distinguish them (except for the difference in A280/A260 which is minor, and can't be trusted). You may have introduced RNAses in your DNAse treatment.
May be, but if we assume a nice condition, is this is normal that your RNA quantity reduced after DNAse digestion?
No. But you can lose RNA in the cleanup afterwards.