Hi Jay, I've used pCS2+ quite a bit, and I would have to disagree that it is a low copy plasmid in general, as we would routinely get mg quantities from midi/maxi preps. However, 5 - 10 ug/ul sounds rather extreme. You might get 50 ug total from your mini prep if you're lucky (therefore 1 ug/ul). If you need more, you'll need to do a midi/maxi prep and then concentrate your DNA via EtOH precipitation and resuspension in a lower volume after you prep the plasmid. Hope this helps. Good luck!

Hi Jay, I've used pCS2+ quite a bit, and I would have to disagree that it is a low copy plasmid in general, as we would routinely get mg quantities from midi/maxi preps. However, 5 - 10 ug/ul sounds rather extreme. You might get 50 ug total from your mini prep if you're lucky (therefore 1 ug/ul). If you need more, you'll need to do a midi/maxi prep and then concentrate your DNA via EtOH precipitation and resuspension in a lower volume after you prep the plasmid. Hope this helps. Good luck!

Thank you Michael. My bad. I saw somewhere that it is low copy (~5 ). I will try to do the concentration with EtOH. I am also thinking of doing a PCR on the plasmid and getting the fragment out along with the SP6 promoter. that should work for my in vitro transcription I think. Thanks

I agree with the comments given by Michael. You can achieve the target amount of DNA using Ethanol precipitation from combined batches of minipreps, midipreps or maxipreps.

Thanks Alemu, I will also try to combine batches.

Always a good idea to double check that you are using the right plasmid and antibiotics!

To obatin the amount (5-10ug/ul), I usually use 'Midi' preparation. If you don't want to spend the money on Midi kit, you can use miniprep. Run several miniprep, then merge the eluant together. If needed, concentrate (ex. using Speedvac) the merged eluant to a higher concentration for use.

Thank you Yuan. I did that and speedvac the eluent then got about 300ng/ul. Another thing I was afraid of with the speedvac is the effect it might have on my plasmid. I will give it a shot with more eluent anyway. Thanks

Hi Jay Peters,

The miniprep is available for isolating small amounts of plasmids (up to 25 μg), Maxipräp is suitable for larger amounts of up to 0.5 mg, up to 2 mg the Megaprep and up to 10 mg the Gigaprep.

Best regards

Thanks Ulrich Koenninger. It just wasn't giving me the expected amount. However, for my specific purpose (in vitro transcription) I was able to find a way around the plasmid isolation. Thanks again

To obtain larger amount of low copy numbers, we used our "Yield Booster" approach where we would use more biomass per resin volume. This is though more tricky than it looks as if this is not done right, your yield will actually drop.

Send us your plasmids as we can prep them for only a fraction of the price offer by other companies. You actually save money if we do it for you! By using our own proprietary protocols, we can not only offer the best price to our customers but also obtain better results than you would with a kit in terms of DNA quantity and quality. See for yourself at https://www.biozilla.bio/plasmid-dna-purification