Storage Recommendations - Agilent Technologies BioHPLC series User Manual

Cleaning Your Column/Extending Column Life
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5. Discard column or consider stronger conditions, e.g.
75% acetonitrile: 25% isopropanol.
6. Increase to 100% isopropanol, 100% methylene chloride or
100% hexane (if you use methylene chloride or hexane, you will
need to flush the column with isopropanol prior to use and before
returning to your mobile phase as it is not miscible with aqueous).
Aggressive cleanup cycles using 80% 1 M NaOH or 1 M HCI with
20% organic can be used with the PLRP-S columns.
For columns with 1.8 µm particles, do not backflush the column –
can attempt the cleanup procedure as detailed above but maintain
direction of flow.

Storage Recommendations

In general, columns may be safely stored for short periods in most
mobile phases. Long-term storage of silica-based, bonded phase
columns should be in a pure organic solvent. If the column has
previously been used with a buffered mobile phase, the buffer
should first be removed by purging the column with 20 to 30 column
volumes of a 50:50 mixture of methanol or acetonitrile and water,
followed by 20 to 30 column volumes of the pure solvent. Before
storing, end-fittings should be tightly capped with end-plugs to
prevent packing from drying out.
ENGLISH
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