13 replies to this topic

[Luria Bertani]

Hello forum,

I've been using QIAGENs miniprep kit to prepare plasmid DNA from E.coli cells. All is good except that I always find that I run
out of columns to catch the plasmid DNA and thus I have lots and lots of reagent over but have to buy an entire new kit if I
want to continue to make. The kit itself is super-expensive and all I want are more columns.

I rang up QIAGEN and asked if I could buy more spin columns - nope. They're the limiting component in the kit, they're expensive
to manufacture, they're not sold separately, "and that's what I was paying for" and "we put in excess columns in there..." I was told.

Not happy!

Well I can't be out wasting my money on entire kits that cost hundreds and hundreds of dollars when all I want is just more
spin columns. Does anyone have any suggestions for alternative plasmid prep kits where I don't have this problem / a
ren't milked for all the cash?

Thanks

LB

[ascacioc]

Macherey & Nagel sells the columns separetely. We also have the same problem you described. Plus, buffer A1 runs first out among all the buffers. Now we prepare it ourselves. It is a simple TE buffer + RNAse.

Andreea

[Luria Bertani]

YES!! I noticed that the A1 buffer runs out early as well.

[leelee]

Huh...I've never looked at it that way...I've always thought of the extra solutions as a bonus.

I happily use the excess resus, lysis and neutralisation buffer to do quick mini preps (and ethanol ppt the dna) for screening etc etc and then just use the columns on stuff that I need to be clean for future applications.

Its true the columns are the expensive part, so I think even if you could purchase them separately, they would be almost as expensive as a new kit anyway.

Isn't it normal to provide x amount of the expensive component, and then the rest of the (cheaper) reagents in excess?

Its like when you buy an enzyme and get excess reaction buffer- I would never think to be annoyed that they hadn't given me only the exact amount I need.

Have I been looking at this the wrong way around all these years?

Just my 2 cents

Edited by leelee, 15 August 2012 - 12:08 AM.

[Julio-Claudian]

As a greenhorn here, I remember reading about reusing spin columns. I don't know how well a 'reconditioned' column will perform [compared to the new ones] but if anyone's interested: http://www.protocol-...posts/6134.html

Edited by Julio-Claudian, 15 August 2012 - 02:21 AM.

[phage434]

Epoch labs also sells inexpensive columns, and instructions on making the reagents.

See also: http://openwetware.o.../Qiagen_Buffers

[hobglobin]

Some companies sell kits for regeneration of silica columns and also buffer sets such as Applichem

[ascacioc]

I personally believe that the only thing worth buying from the kits are the silica columns. Anything else is just simple buffer you can make yourself. Buying a TE buffer from a company is a total waste of money.

In the old times (like 10-15 years ago) they did not have all the fancy kits. They only had the protocols in Sambrock and Maniatis Molecular cloning and they minipreped just fine:) But those protocols result in a quality not appropriate for sequencing (I had bad experience with that). But for most of other applications, you save lots of money with them. Just to put it in numbers: 250 columns are 125€ while the kit with 250 columns + some simple buffers is 243€.

@phage434: thanks for the Qiagen buffers. Our technician will be blissful tomorrow:)

Andreea

[Trof]

Yeah I also consider Qiagen kits being merely a bunch of columns with buffers in excess, it's definitelly the most expensive part.

I heard about Epoch columns as being good enough replacement for original Qiagen, when used with home made "Qiagen" buffers from Openwetware, I even read somewhere on their pages that these are exactly the same columns, just not branded, but can't find this claim now. I was planning to test it as an alternative, but kind of haven't time for that yet.
I think this is safer way than to regenerate columns, you can't be sure you don't cross-contaminate.

We were looking for some cheaper alternatives for gel extraction that we do a lot, bought a Geneaid kit that's like 3 times cheaper, but testing showed 2x lower yield from the same amount on gel. Still it seems fair for the price, but the problem was not only overal yield was lower, but also the elution volume was bigger, so the concentration was actually out of the trustworthy spectrophotometric measurement. So, goodbye cheap kit, I better take my chances in sequencing reactions with MinElute.

However, Geneaid also offers plasmid miniprep kits, that are also cheap and though the yield is probably also lower than Qiagen would be, that is not that important in this case, it's enough because we usually do minipreps only for checking if the plasmid is right.

[hobglobin]

phage434, on 15 August 2012 - 05:45 AM, said:

Epoch labs also sells inexpensive columns, and instructions on making the reagents.

See also: http://openwetware.o.../Qiagen_Buffers

did anybody try out this is this regeneration protocol at the end of the page? Is it good?

[bob1]

i still do my minipreps the old fashioned way, just add a chloroform extraction and PEG pptn step to get sequence quality DNA.  It really doesn't take much longer than the kits, as you can do other things during the precipitation steps.

Also note that buffer p2 on the openwetware page should be made fresh each time as the NaOH gets neutralized by CO2 absorption from the air.

I also used to work in a lab that made their own (Promega) wizard miniprep columns using cheap filters and diatomaceous earth.  I can't remember what sort of preparation was required though.

[pito]

ascacioc, on 15 August 2012 - 08:00 AM, said:

I personally believe that the only thing worth buying from the kits are the silica columns. Anything else is just simple buffer you can make yourself. Buying a TE buffer from a company is a total waste of money.

In the old times (like 10-15 years ago) they did not have all the fancy kits. They only had the protocols in Sambrock and Maniatis Molecular cloning and they minipreped just fine:) But those protocols result in a quality not appropriate for sequencing (I had bad experience with that). But for most of other applications, you save lots of money with them. Just to put it in numbers: 250 columns are 125€ while the kit with 250 columns + some simple buffers is 243€.

@phage434: thanks for the Qiagen buffers. Our technician will be blissful tomorrow:)

Andreea

Could be, but I always wonder: is it really worth the effort to make it yourself? You have to prepare it, it takes time too.
And if you need to make things fresh before using it.. I dont know.. it seems a lot easier to just use the kit...
And there will always be a difference in preparing it, esp if different people prepare the buffers.

I do agree on buying new columns (just columns) if you still have enough buffer left, in stead of always buying complete new kits.

[kw917]

Yes, we had same problem before, always run out of columns and have leftover solutions for DNA and RNA kits.  We have been using Enzymax RNA/DNA mini spin columns for the past 6 or 8 years and they are so cheap, $39/100 DNA columns and $59/100 RNA columns .  Now, they are selling a very tiny column call micro spin column for RNA and DNA, you can isolate DNA from single colony and elute the DNA in 5ul ddH2O.

http://enzymax.net/L...umn_DNA-RNA.htm

[Lisa Hsu]

I buy mini-prep kit from a Korean company http://solgent.com/english/pro1_2_1_01
Very cheap, easy protocol, and gives me clean product with high yield.
They do sell column and reagent separably