IonPac NS1 Manual
Document No. 034024-06
Page 34 of 35
APPENDIX B - COLUMN CARE
B.1 Recommended Operation Pressures
The maximum recommended operating pressure for IonPac NS1 columns is 4,000 psi (27.57 MPa). Operating a column above
its recommended pressure limit can cause irreversible loss of column performance.
B.2 Column Start-Up
The IonPac NS1-5µm is tested with, and shipped in, 26% acetonitrile/4.0 mM tetrabutylammonium hydroxide. The IonPac NS1-
10µm is tested with, and shipped in, 28% acetonitrile/3.0 mM tetrabutylammonium hydroxide. The column should be thoroughly
washed with 80% acetonitrile/deionized water until the background is below 1 µS before switching to other eluents.
Prepare the eluent shown on the test chromatogram, install the column in the chromatography module and test the column
performance under the conditions described in the test chromatogram. Continue making injections of the test standard until
consecutive injections of the standard give reproducible retention times. Equilibration is complete when consecutive injections
of the standard give reproducible retention times.
B.3 Column Storage
For short-term storage, the strongest eluent in use can be used as the storage solution.
For long-term storage, the strongest eluent in use should be used as the storage solution. Flush the column for a minimum of 10
minutes with the storage solution. Cap both ends securely, using the plugs supplied with the column.
B.4 Column Cleanup
The following column cleanup protocols have been divided into three general isocratic protocols to remove acid-soluble, base-
soluble or organic contaminants. They can be combined into one gradient protocol if desired but the following precautions should
be observed.
Always ensure that the cleanup protocol used does not switch between eluents which may create high pressure eluent interface
zones in the column. High pressure zones can disrupt the uniformity of the packing of the column bed and irreversibly damage
the performance of the column. High pressure zones in the column can be created by pumping successive eluents through the
column that are not miscible, that have eluent components in one eluent that will precipitate out in the other eluent or by using
an acid eluent followed by a base eluent with may create a neutralization pressure band. The precipitation of the salts in solvents
during column rinses can result in very high pressure zones. High viscosity mixing zones can be created between two eluents
having solvents with a very high energy of mixing.
When in doubt, always include short column rinse steps to reduce the solvent content of the eluent to 5% levels and the ionic
strength of the eluent to 50 mM levels to avoid creating high pressure zones in the column that may disrupt the uniformity of the
column packing.
