Recycle Those DNA Extraction Columns
You know those ridiculously priced and throw-away DNA mini, midi and maxi-prep columns? Well the good news is that you can actually re-use them if you are reasonably careful at regenerating them, with this simple and cheap method described in detail by Nagadenahalli B. Siddappa in Biotechniques in 2007.
Apparently these columns can be reused up to 20 times… perhaps more a guesstimate than a real number, but hey, who’s complaining?
Essentially the columns are treated with 1M HCl overnight, rinsed extensively with dH2O and then re-equilibrated with buffer from the kit you use (e.g. Qiagen QBT). If you are worried about finishing the buffers in the kits, look in the back of the manual, there are often simple recipes about how to remake them.
The authors allay concerns about plasmid carryover contamination by assaying for plasmid using RT-PCR and transfection assays which all showed zero carryover between recycled uses of the columns. In fact they showed that the plasmid DNA had been chemically sheared into low molecular weight fragments and could not be used as a template.
They also stated that prolonged exposure to 1M HCl (1 month) did nothing to the binding capacity of the columns, so even if you forget about it, there is no need to stress.
Our lab has modified the protocol to include passing warm water through the treated columns when regenerating to ensure that all DNA and any other contaminants are removed. Also pre-warming the elution buffer to 42oC or thereabouts seems to increase the elution of any plasmid DNA bound to the column, although what extra compounds it releases is unknown but probably negligible.
It may be our imagination, but we have often gotten higher yields of plasmid DNA from a treated reused column, than a new one.
Go ahead, stretch those budgets further.
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Hi Patrick. Drop me an email using the contact form so we can talk about that.
Cool, I was about to drop you an e-mail and suggest this as a futur article.
Btw, I’m still up for the ligation indepedent cloning vector project
With the miniprep columns, I would be very careful putting them in any stirring solution, the matrix is not the same as in the bigger columns, perhaps just a good soak would be sufficient, then again, perhaps good old soln 1 2 and 3 is sufficient for screening.
Well, looks like I know what I’m going to be doing with my down time this week.
I definitely want to start doing this in my lab, and just have a couple of questions so I do this right, both pertaining to the final steps. I haven’t worked with HCl much (besides in my stomach), but I know it’s not something you want to play with and obviously needs to be gone from the preps. My first question is since the entire prep soaks in HCl overnight, what’s the best way to clean it off, inside and out (squirt it with water, dip it in water, etc)? Secondly, I don’t use a Qiagen kit with QBT buffer, I use the pcr and spin minipreps, and am currently in the process in changing from Qiagen to Zymo. I’ve found the recipe for the re-equilibrating QBT, but I don’t think a component of my kits resembles that recipe. So if it matters, should I use a solutions from my kits (if so, which one) or make me some QBT and use it? Sorry for the density, and thanks in advance.
Hi,
How did it go with switching to the Zymo columns? I had but it did not go that well for me. I’m wondering if someone else had the same experience or if it was that I’m just a newb