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glass wool replacement - for home-made Sephadex columns (Apr/30/2008 )

Hello all!

At our lab we use home-made Sephadex G-50 columns with glass wool to prevent the Sephadex from escaping.

However we have run out of glass wool and we are not able to locate any seller for this in our area... is there a replacement for this? Any other material that can be used for this purpose?

Any ideas?

Thanks in advance.

-agusman-

A piece of prewet cottom ball, or even kinwipe (tissue wiper) maybe able to so the job, if you dont mind some sample absorption by these plug materials.

-genehunter-1-

if you use cotton, be careful that you don't overcompress it or you will severely inhibit flow.

what are you using to make your columns? do they have tapered bottoms or are they open?

if they are open bottoms and you close them with rubber stoppers then you can use many things to support sephadex.

we used to use two layers (crosslaid) of "handi-wipes", nylon mesh, etc.

-mdfenko-

Aquarium Filter Floss (FF) is an alternative to silanized glass wool (SGW) as a porous support matrix. It's cheap and available at pet shops and aquarium stores. Also much safer to handle than glass wool. (R. Levine 1994, BioTechn 17 (1) 67.)
Filter Floss is a nylon fiber material. FF is easy and safer to work with, is chemically inert and cheap. It can be autoclaved and does not need to be silanized. FF gave a 95% recovery of 32P-labeled DNA. SGW gave 88% recovery. Non-specific binding in another experiment gave 0.1 and 1.2% respectively.

-tfitzwater-

QUOTE (mdfenko @ Apr 30 2008, 11:01 AM)
what are you using to make your columns? do they have tapered bottoms or are they open?


Thanks for your replies.

We use 1,5ml eppendorf tubes with a hole at the bottom. We use it to filter 32P-labeled DNA. You think cotton or tissue paper would work for this?

should I autoclave it and dry it first?

-agusman-

QUOTE (agusman @ Apr 30 2008, 11:06 AM)
Thanks for your replies.

We use 1,5ml eppendorf tubes with a hole at the bottom. We use it to filter 32P-labeled DNA. You think cotton or tissue paper would work for this?

should I autoclave it and dry it first?

i like tfitzwater's recommendation. it is a direct replacement for glass wool and would be used the same way.

if you can't go out to get it and need it right away, then use the cotton (be careful not to pack it too tight). i don't think that tissue paper would be able to stand up against the g forces (if you are making spin columns) or the flow (if you are using gravity flow).

unless you need to maintain sterility, i wouldn't worry about autoclaving the cotton.

-mdfenko-

if you can find glass beads with the right size, it may work. I did that before.

-genehunter-1-