column volumes
Posted: Wed Sep 05, 2007 2:33 pm
Hi can someone please tell me how to calculate the number of column volumes of mobile phase passing through the column?
Thanks
Liv
Thanks
Liv
Dear Olivia
The number of column volumes can be calculated knowing the total volume of the mobile phase that you use to purge the column and the column void volume (specified by manufacturer, see the flip of paper that comes with your column).
Number of column volumes = (purge volume of mobile phase)/(column void volume)
If you purge your column with 10 mL mobile phase (e.g. 10 minutes with 1mL/min flow) and your column void volume is 0.8mL then number of column volumes (that you purged you column after 10 min with 1mL/min flow) is 10mL/0.8mL = 12.5 column volumes.
Or, if you want to purge your column with 20 column volumes of mobile phase and your column void volume is 0.8mL, then total volume of mobile phase that should purge your column is 20x0.8mL = 16mL (purging 16 minutes with 1mL/min flow)
Best regards