Dear all

We are using prep. HPLC for the first time (until now we used flash chromatography). We would like to separate small synthetic peptides in a 10 gramm scale per run. Our HPLC system has 100 ml/min pump heads. max. pressure is 140 bar.
What kind of column size and packing material would you recommend ?
Any comments regarding flow rates and back pressure ?
Thank you.

you can use a ymc c-18 (ods) column of 500mm*50mm,20-30µ size particles
for your application for best possible results and recovery.

Hello,

bevor you purchase a prep. column, please do your separation on an analytical column, 4,6x250 for example. For small peptides you can go with a 80A, 100A or 120A material, high purity silica based C18! First try a 5µm material, than a 10µm material in an analytical size. After you are satisfied with resolution etc. increase sample load step by step, until you reached the break through concentration. Than decrease sample load by 10%. This is now your starting point to do upscaling.
What do you do with your peptides after separation? Do you use them for clinical studies?
Is it realy neccessary to do it in one shot, the 10g. How often you will do this separation? It's all important for the money you have to invest for such a column.
If you start with a 4,6ID column, and you go to an 50mmID column, scaling up factor is 120! This stands for sample load, flow rate, injection volume and amount of packing material.

Hope this helps.
Gerhard Kratz