Low 260/230 ratio in my RNA - (Dec/11/2009 )
I`ve isolated RNA with the Promega kit. I measured the concentration etc. with Nanodrop and I have low
260/230 ratio`s ( around 1.4-1.8). The troubleshooting section of the kit
said that there is to much guanidine thiocyanate and that I should precipitate my RNA with NaCl and ethanol
at -20 for 30min.
I already have a low concentration of RNA so I`m a bit susceptible to do this because it eventually again
will decrease my RNA concentration.
Will this guanidine thiocyanate comprimise my RT-PCR results? Should I leave my samples
the way they are or should i perform the additional step and probably loose RNA?
i would not worry to much about the low A260/230 ratio ...you will use your template diluted for the RT-PCR, therefore it should be no problem at all. If you experience problems after a first try you can try to re-purify your sample.
1.4-1.8 is not ridiculously low (2 is optimum). This could be due to guanidine thiocyanate or ethanol in your washes. I would not worry too much about it. What manufacturers are you using for RT-PCR?
Baars01 on Dec 15 2009, 06:54 PM said:
Agree. Since you are using for RT-PCR it should be fine and not disturb the reactions too much.