Chromatography Forum

Hello, sirs!

Recently, we purchased a Hi-Plex Ca (Duo) column to analyse carbohydrates.
The supplier methodology indicates a 0.6 mL/min flow at 85 ºC. Unfortunatelly our HPLC can't reach this temperature so we tried to do it at 80 ºC, but at this temperature we are unable to exceed a flow of 0.24 mL/min because of the column maximum
allowed pressure (50 bar). Could this 5 ºC diference influence so much the pressure? Can we increase the flowrate in any way?

Thanks for your help!

5 degrees should *not* make that much difference in pressure. The reason for the elevated temperature is to speed up the anomerization of glucose so that you don't see a split peak.

If you have checked the obvious (a blockage somewhere in the system), and it's a new column, you need to contact your supplier for a replacement. If you have used the column for some time, you can try backwashing the column.