To ensure rapid equilibration of an HPLC column, the change of eluents should be performed in several steps (see also the tips below).
Before using eluents, always rinse the column with 25:75 acetonitrile-water at least ten times the column volume.
After changing to the desired eluent, equilibrate the column with at least ten times the column volume of eluent before the first injection. The following formula is used to calculate the column volume :
Volume V = π r2 L
with V = column volume [ml]
r = column radius [cm]
L = column length [cm]
Some basic rules when switching to solvents/solvent mixtures: