Concentrating RNA advice needed - (Aug/23/2005 )

I need to concentrate some RNA that i have a very finite amount of and would like to get some people's opinions on what they like to do in such situations.

I have about 10ug of RNA in 100uL of ddH20 obtained from RNAEasy micro kit. I need to concentrate this to about 10uL without any loss in quality. This will be used for a microarray. Getting more RNA is not really an option. I need at least 8-9ug/10uL as my final solution, so i can afford to lose some RNA but not much. Degradation would be the worst though.

I am hesitant to use a speed vac to just concentrate it because i have lost RNA that way before and this is too important to lose.
Most centricons have a significant retention volume so it seems i would end up losing half my sample with a centricon.
I haven't really thought much about just doing an ethanol precipitation then resuspending.

I will try anything first on non-important samples.

I want to figure out what the best option is before i actually commit my sample to it.

Thank you in advance

Do an ethanol precipitation o/n at -20C then spin for 30 minutes. You will get close to 100% recovery.

Daniel

Use less BigDye mix