Agilent InfinityLab Poroshell 120 HILIC Guide D'utilisation page 12

Cleaning Your Column/Extending Column Life:
HILIC Columns
Samples should be filtered before injecting on the column. This is particularly
important for the ZORBAX RRHD HILIC Plus column, as the column inlet
frit is nominally 0.5 µm and samples should be filtered through a 0.2 µm
sample filter. If solvent flow appears to be restricted (unusually high
column backpressure), check first to see that solvent flow is unobstructed
up to the column inlet. If the restriction is prior to the column, replace the
appropriate piece of tubing or filter that is plugged. If the column is plugged,
InfinityLab Poroshell 120 HILIC can be backflushed with 20-30 column
volumes of mobile phase. The RRHD HILIC column cannot be backflushed.
To remove strongly-retained materials from the column, flush the column
with a strong solvent which in HILIC mode, is water.
InfinityLab Poroshell HILIC-OH5 columns may be regenerated by
flushing with 50/50 acetonitrile:50 mM ammonium acetate at a low
flow rate for at least 3 hours. Then equilibrate with mobile phase.
InfinityLab Poroshell HILIC-Z columns may be regenerated by flushing with
50/50 acetonitrile:10 mM ammonium acetate at 20% of normal operating
flowrates for at least 3 hours. Then equilibrate with mobile phase.
Storage Recommendations: HILIC Columns
Acetonitrile:water (90:10) is recommended as the long-term storage solvent
for HILIC columns. Before storing the column, tightly cap the end fittings
with the end plugs to prevent the packing from drying out. Columns may
be safely stored for short periods in most HILIC mobile phases. However, to
protect equipment, it is best to remove salts from the instrument and column
by purging the column with the same mobile phase without the buffer (for
example, using 90:10 ACN:H O to remove a 90:10 ACN:0.01M formate
2
buffered mobile phase). Re-equilibration is faster with the original mobile
phase when using this approach, but several (3 to 6) injections should be
made to verify column equilibration.