Hi all,

I just stumbled across several boxes of Qiagen Rneasy Kits (the large ones).
But they are already 3 years old
Has anybody any experience with old Rneasy columns? Qiagen guarantees for 9 month and I know for Qiaquick columns that they are essentially dead after 1 year
These kits are not what I call cheap, therefor I would be glad to use the old ones. My first tests were not encouraging, though.
Any suggestion is welcome!

Krümel

well i would try with a non urgent and tough RNAs.
I think that buffers should have changed their pH, guanidine isothiocyanate (important for binding) should have been altered...
so if your exp are either important or tough, don't use these columns before test.

Thanks Fred,

in your opinion are only the buffers problematic or can the membranes stop working too?

Krümel

well membranes are supposed to e dry.
If conditions of stroage (15-25°C, low humidity) were ok, then the columns should be ok.

Thanks again Fred!

You were right, just the Buffer containing guanidine isothiocyanate did not work anymore.
I now use Trizol and directly bind the aqueous phase to the column after I have mixed it with the same amount of 100% ethanol. I just skip into the RNeasy protocol from there (washing and elution) and now have a good yield.

Krümel