Source for Wizard/Merlin midiprep plastic columns?

Hello everyone,

We use these columns to do a homemade Merlin/Wizard-type midiprep. (In
fact we just reuse the columns after getting rid of the resin.)
Unfortunately, we've lost our last of these columns. Promega has
stopped selling the type that we use -- they've seemingly redesigned
the columns so as to prevent reuse. (They now have the resin collected
in a narrowed part of the column toward the bottom, which you are
supposed to physically separate in order to later elute... clever
devils! Unfortunately, these new columns also work extremely poorly.)
The type that we use is perhaps 50 mL total volume, bottom maybe 4mm
diameter, bottom opening maybe 2mm diameter (this is important so they
fit into the vacuum manifold). They also have a relatively thick
plastic frit at the bottom (important so that resin can't get through),
which is the full size of the column diameter. Anyone know of a source
for these columns?

Thanks,

Jenny

In article <fqg455$pn9$[Only registered users see links. ]>, Jenny F. <[Only registered users see links. ]> wrote:

Just a suggestion:

Buy porous polyethylene sheets that are available from many
suppliers in various pore sizes; 30-90 micron is most applicable).
I.e., [Only registered users see links. ]
(Or just reuse top and bottom frits from Qiagen's maxi prep
columns; that's what I do).

Then all you need is syringes and a cork borer set. Bore out a frit
of appropriate diameter and shove it down 3 ml syringe (blunt end
of a 5 ml plastic pipette work best for that). Then, if you insist
on having a wider extension for larger volumes, your choice
is unlimited - a standard luer connection on all syringes fits very
tightly into 3 ml syringe - so any syringe barrel (10, 20, 30, 60 ml)
can be used. For unrestricted flow through such improvised
column extension, it helps to use a cork borer to remove
internal luer connection from it.

Such a column (3 ml syringe) can be placed into 15 ml
Faclon tube and spun at up tp 2,000 rpm in a typical
swinging bucket rotor suitable for such tubes.

I use this setup and many of its variations routinely for
protein purification and for making spin columns for buffer
exchange. The parts (3 ml syringes with frits and larger
syringes with a widened exit) can be reused basically
indefinitely.

Alternatively, if your resin volume is < 0.7 ml, all luer
lock syringes snag very tightly into Qiagen's pink
(but not blue) columns.

DK