Agilent InfinityLab Poroshell 120 HILIC Guide D'utilisation page 8

Note: All silica-based packings have some solubility in pH >6 aqueous
mobile phases. When using silica-based columns at pH >6, best column
lifetime is obtained at lower temperatures (40 °C Max) using low buffer
concentrations in the range of 0.01 to 0.02 M.
Normal-Phase Column Method Development Notes
The stationary phase is polar in nature and is best used with nonpolar mobile
phases such as methylene chloride/hexane or isopropanol/hexane mixtures.
Increasing the amount of the polar component in these mixtures typically
reduces the retention time of the sample.
Column type
ZORBAX NH2
Polaris NH2
ZORBAX Rx-SIL
ZORBAX SIL
Pursuit XRs Si
Polaris Si-A
InfinityLab Poroshell 120 EC-CN
ZORBAX Eclipse XDB-CN
ZORBAX CN
Method development notes
Retention decreases as the polarity of the mobile
phase increases.
Many column volumes of mobile phase are
necessary for equilibration to occur after changes in
mobile phase composition. The number of column
volumes required depends on the system in use and
can be as high as 50 to 100 column volumes.
Unbonded silica columns are very sensitive to trace
amounts of water in solvents and sample, so care
must be taken to maintain consistency for method
reproducibility. When gradient elution is employed,
both primary and secondary solvents should be
modified with alcohol or acetonitrile and at least
30 columns of solvent should be allowed to flow
through the column after completion of each run.
When switching between solvents, first rinse the
column with a mutually miscible solvent such as
isopropyl alcohol.
Agilent InfinityLab Poroshell 120 EC-CN and
ZORBAX Eclipse XDB-CN columns are shipped
with reversed-phase solvents, but can also be used
in normal phase applications after flushing with
isopropanol.
Retention decreases as the polarity of the mobile
phase increases.
The rapid equilibration of this bonded phase with
mobile phase often makes it more convenient to
use this column than a silica column, especially for
gradient elution.