Chromatography Forum

Hello,
I'm after some advice regarding trying to use an analytical LC system to do some low/medium pressure (semi)preparative LC. I've a Varian HPLC system (240 pump, 325 UV detector and 410 autosampler modules) and I was wondering if it wouild be possible to use this system with a low/medium pressure lab packed glass column. I want to do this because I am currently using an affinity medium (lab made and based on Sepharose 4B) to isolate an enzyme from some clinical samples in a SPE format. This is rather wasteful (as I don't reuse the SPE columns), so I would like to investigate prep LC as an alternative. Searching through the archives I can see that components like UV flow cells etc must be compatible with a higher than normal flow. The type of columns I hope to use (and have used sucessfully in a previous job, but with a dedicated medium pressure prep LC) are those such as the XK series from Amersham. If I were to try and connect this lab packed (glass) column (2.6cm bore, 20cm long) to the above pump (flow rate approx. 2-3 ml/min) would the column break? Would there be any other issues that might make this a non-starter? Any help/advice would be much appreciated.
Thanks.

You need to figure out, what the post-column backpressure will be at the flow rate that you are planning to use. A glass column should come with a pressure rating. If the post-column pressure is too high, you either need to investigate what you can do about the detector, or use a glass column with a higher pressure rating, or abandon the idea and go to steel.

Thanks for the info.
Dan.

We are using empty columns from GE Healthcare (formerly Amersham) and Omnifit. The ones from GE do not stand more than a few bars back-pressure, but the ones from Omnifit have a higher pressure rating (depends on the diameter). I like them better: they don't have these rather annoying M6 fittings with flanges, they are available for with both fixed and variable end pieces, all parts in contact with the solvent are made of PTFE or glass, so they should be compatible with organic solvents as well. http://www.omnifit.com