DNA/RNA isolation from small starting material? - Which is the best method RNeasy, Trizol, etc? (Oct/13/2006 )

Hi, my research lab is working with flow sorted lymphocytes. However we've been having problems getting good, clean RNA/DNA isolation. We tried the AllPrep RNA/DNA Qiagen Kit as well as the TRIZOL reagent and tested cell counts from 10k, 20k, 50k, 100k, 200k. However, the results were inconclusive and has given a lot of headaches. Can someone with background on this subject offer some advice?

Also if you know any papers already testing which method is better, RNeasy or TRIZOL, I would appreciate reading it. Thank you.

Generally, the quality of simutanously isolated nucleic acids is not as good as those isolated separately. We use TriReagent for RNA isolation and subsequently DNA isolation. the RNA is fine but the DNA is always at very low concentrations.

try picopure dna extracrion kit from www.arctur.com. claims to be able to get dna from 10-1000 cells.