There is no general value for any kit yield. If you are looking for general value, check the manual, otherwise yield differ from experiment to experiment.

Plasma doesn't have much in it: it's a cell free fluid.

What RNA it does contain is...mostly miRs, and those are small (so don't contribute much in terms of RNA mass).

I extract from serum and typically get yields of "I am not even going to bother speccing this" (i.e. looow), so I just base my reverse transcription on volume rather than quantity. I can confirm that even [RNA] too low to measure still has LOADS of miRs.

Dear victoria..i am using similar kit. extracting total RNA from frozen plasma. my experience is similar with a low amount total RNA. the range of RNA concentration is about 20 - 100 ng/ul and the purity also within 1.3 - 1.7 (260/280 reading). i am spending so many months to getting the idle value, changing one kit to another kit, improvise one step to others steps. i found the qiagen kit more practical then others.

i am agree with John.

I faced the same issue and when enquired from Qiagen, they said you should not use Nanodrop.the only way is to use Bioanalyzer.