Suspected bad batch of XLR70 sequencing reagents!!!!!
Beware, as of 19th July 2012 Roche have said that there MAY be an issue with XLR70 sequencing reagent Lot. number 93859420.
They can't say at present what the issue may be or what reagent, only a suspicion based on two sites and won't be pressed on the last 6 months at least of inconsistent and/or sub-standard runs, or the previous similar problems in 2010 when it turned out to be PicoTiter plates.
Considering the machines were serviced, and we ran their own 454 controls which failed the only other option I can foresee could be possible Flx+ upgrade issues, as we've experienced issues since ours were. Although we saw similar issue with the standard Flx machines as well.
It may of course possibly be (according to Roche):
1. Our tissue lyser is noisy. It was new last year and the noise level is the same as it's always been, although we have moved labs and the bench it sits on now may reverberate more so we have used a rubber mat to eliminate this now.
2. We don't use Eppendorf pcr plates and caps, which whilst they may be the only ones Roche "accredit" (they haven't showed me the test results pertaining to the tests I presume they carried out to ascertain this, but I have asked), we've only ever used Star lab plates and adhesive seals. There hasn't been a technical bulletin released even though they have been aware of what plates we have been using for 5 years. Although they will tell you that some customers have been "amazed" by the difference (a bit like when you change soap powder to a leading alternative I presume....). I would have thought that if this was the case it would have become a technical bulletin.
3. Gently drawing up 200ul emulsion with an Eppendorf repeater pipette (recommended and still ok to use you'll be happy to know) and gently dispelling again to remove the air bubble at the top of the tip (as this compresses differently than the emulsion and will cause leaking/drops) can break the emulsion microreactor, yet subsequent expelling of said emulsion in 100ul aliquots using the trigger at a far greater speed doesn't have an effect.
Phew, that's a relief and very satisfactory.
They can't say at present what the issue may be or what reagent, only a suspicion based on two sites and won't be pressed on the last 6 months at least of inconsistent and/or sub-standard runs, or the previous similar problems in 2010 when it turned out to be PicoTiter plates.
Considering the machines were serviced, and we ran their own 454 controls which failed the only other option I can foresee could be possible Flx+ upgrade issues, as we've experienced issues since ours were. Although we saw similar issue with the standard Flx machines as well.
It may of course possibly be (according to Roche):
1. Our tissue lyser is noisy. It was new last year and the noise level is the same as it's always been, although we have moved labs and the bench it sits on now may reverberate more so we have used a rubber mat to eliminate this now.
2. We don't use Eppendorf pcr plates and caps, which whilst they may be the only ones Roche "accredit" (they haven't showed me the test results pertaining to the tests I presume they carried out to ascertain this, but I have asked), we've only ever used Star lab plates and adhesive seals. There hasn't been a technical bulletin released even though they have been aware of what plates we have been using for 5 years. Although they will tell you that some customers have been "amazed" by the difference (a bit like when you change soap powder to a leading alternative I presume....). I would have thought that if this was the case it would have become a technical bulletin.
3. Gently drawing up 200ul emulsion with an Eppendorf repeater pipette (recommended and still ok to use you'll be happy to know) and gently dispelling again to remove the air bubble at the top of the tip (as this compresses differently than the emulsion and will cause leaking/drops) can break the emulsion microreactor, yet subsequent expelling of said emulsion in 100ul aliquots using the trigger at a far greater speed doesn't have an effect.
Phew, that's a relief and very satisfactory.
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