TruSeq Stranded Total RNA final sample storage

[Qualiphar]

Dear Seq-ers

I was wonderding if somebody has any experience with, if any, sample quality loss after preparing your samples with the TruSeq Stranded Total RNA kit? Illumina recommends maximal storage for one week, exceeding this time will cause quality loss (or at least they did not test the quality after one week). Therefore, is it possible to keep your final prep product for two/three weeks on -20? I have some HiSeq runs scheduled and it would be way easier to do the sample prep for all the runs spread over time.

Thank you in advance for answering!

[kmcarr]

Dear Seq-ers

I was wonderding if somebody has any experience with, if any, sample quality loss after preparing your samples with the TruSeq Stranded Total RNA kit? Illumina recommends maximal storage for one week, exceeding this time will cause quality loss (or at least they did not test the quality after one week). Therefore, is it possible to keep your final prep product for two/three weeks on -20? I have some HiSeq runs scheduled and it would be way easier to do the sample prep for all the runs spread over time.

Thank you in advance for answering!

The protocol appears to make a distinction between completed (post Enrichment but pre QC/Quantitation) and normalized/pooled libraries. For the the Enriched libraries they state store up to 7 days, but for libraries which have been normalized and/or pooled they simply state store at -15°C to -25°C with no time limit given. Perhaps they feel that the added Tween in the normalization buffer is required for long term storage.

Truth be told we have stored enriched but non-normalized libraries for many months at -20°C and they work just fine. If they have been in extended storage it's probably worthwhile to repeat the QC.