Covaris/Hydroshear

[andibody]

Hi,

I know the topic has been discussed before... but we are about to test Covaris and Hydroshear systems.
I would be interested to hear some experiences of people shearing their DNA with one of those. We do mainly ChIP-Seq, having started in February this year.
So far we have been using a Bioruptor but several researchers have had trouble getting their samples down to a reasonable size.

Thanks in advance for any responses and by the way thanks to the ones who run this helpful and informative website.

Cheers
Andibody

[marklar]

I'm sorry that I can't speak about the hydroshear, but I have a colleague who has been testing genomic dna on Covaris vs Bioruptor. There really isn't much of a difference in fragment size so we're planning to go with Bioruptor since it's cheaper and you can process multiple samples.
I've been testing the Bioruptor XL (the larger one that can do up to 48 samples at a time) on long range pcr products and so far it hasn't worked consistently. I've heard from others that it also doesn't work on genomic dna. However, we will be getting the Bioruptor 200 and have briefly tested that before and it works.
There is another thread here about this. http://seqanswers.com/forums/showthr...ight=bioruptor

Can you tell me which Bioruptor system you're using? And what the problems have been...what fragment sizes you're getting? I'd be interested to see what you've tried as I've been varying time and concentration.

best...

[ESEMBE]

Hydroshear replacement from covaris

http://www.covarisinc.com/press_22.htm

Covaris consumable shears DNA to 6kbp - 20kbp fragments
g-TUBE, the latest innovation from Covaris, is a single-use consumable that enables scientists to shear genomic DNA into selected fragments sizes ranging from 6kbp to 20kbp. The only equipment needed is a compatible bench-top centrifuge and a pipette.

g-TUBE uses centrifugal force (the "g" in g-TUBE) to push the sample through a precisely manufactured orifice in the embedded ruby. This produces shearing forces in the sample that fragment the DNA. Fragment size is selected by adjusting the centrifuge rotor speed which alters the flow rate through the ruby and thus the shearing forces. Higher centrifugation RPM will produce shorter fragments and the protocol provide by Covaris contains the settings needed to select a fragment size between 6kbp and 20kbp.

Remarkably, the entire process takes only 3 minutes and up to 24 samples can be processed simultaneously.