how to pack an analytical column

[henriette]

Hello everybody,

I have to pack my own analytical column, because a prepacked one is not available. I want to fill the column with a substance called "hydroxyapatite".
Does anybody know if it is difficult and even possible to do this?
Any tips available?

Cheers, Henriette

[Rafael Chust]

Hummm... there was a company back in the 80's in Czech Republic that used to pack hidroxyapatite columns. Anyone knows if they are still around?

Concerning packing, there are companies selling cheap packing systems, that at least will guarantee reproducibility column-to-column.

Check www.laballiance.com as I think they carry this stuff.

[Mark Tracy]

Packing columns is a bit of an art, and manufacturers are reluctant to give away the secrets. I'll tell you what I can.

First, you need a pump that can deliver about 8000psi at several mL/min. The air-driven pumps from Haskel are the industry standard, but the prep pumps from LabAlliance work also (we use both). Most HPLC pumps don't have enough pressure/flow to pack columns.

Next you need a slurry reservoir. You can buy them from LabAlliance or Isolation Technologies or make your own. This is usually a tube with about 30 mL capacity with an adapter on the bottom. Adapters are also available from the same sources.

Since you are planning to pack a hydrophilic material, you can just suspend it in aqueous buffer. 3-10% by weight will be the right range. The choice of buffer is empirical. You want enough packing material in the slurry to overfill the column by about 1cm.

Attach the column to the reservoir, fill it to the top with slurry, and pump the slurry into the column. You will need a final pressure of at least 6000psi, but the optimum will be empirical.

Are you absolutely sure that you can't buy the column somewhere? You can make a career of packing columns.

[Rafael Chust]

I finally remebered the name - Tessek - and look into their website but it seems they drop off production of these columns.

Anyway, you could check there - www.tessek.com - and send an e-mail to them...

Good luck!

[Chris Pohl]

henriette,

The specifics of how to pack such columns are quite dependent on particle size. Often, if the particle size is greater than 15 micron, one can pack a decent column by simply pulling a vacuum on the column outlet and filling the column with a slurry of the packing material. However, the leading supplier of hydroxyapatite is Bio-Rad. If you check their web site you'll see they sell quite a number of different prepacked columns with this media.

[henriette]

Hello everybody,

Thank you so much for your help and replies to my question.
Rafael: I will check www.tessek.com and sent them an e-mail.
Mark, Chris: Thanks for your explanation. I had contact with LabAlliance, but since I only want to pack a few columns it's not economical to buy their pump/system.
Or I will give it a try myself to fill the column, or I will find a company who can do it for me. I will give it a try!
Thanks again for your support. It was very helpfull!

Henriette