Waters XBridge XP 2.5 µm Columns - Manual (Page 7)

XBridge XP 2.5 µm Columns 7
[ CARE AND USE MANUAL ]
c. Solvents
To maintain maximum column performance, use high quality HPLC
or MS grade solvents. Filter all aqueous buffers prior to use through
a 0.2 µm filter. Solvents containing suspended particulate materials
will generally clog the outside surface of the inlet of the column. This
may result in higher backpressure or distorted peak shape.
d. Pressure
XBridge XP 2.5 µm Columns are compatible with HPLC, UHPLC and
UPLC pressures. Table 6 depicts the maximum operation pressure.
Table 6: Maximum Operation Pressure
Column ID Pressure Range
2.1 mm 18,000 psi [1034 bar]
3.0 mm 18,000 psi [1034 bar]
4.6 mm 9000 psi [620 bar]
e. Temperature
XBridge XP 2.5 µm Columns can be used up at intermediate
temperatures to enhance selectivity, reduce solvent viscosity and
increase mass transfer rates.
Chemistry
Temperature Limit
Low pH
Temperature Limit
High pH
XBridge BEH C
18
80 °C 60 °C
XBridge BEH C
8
60 °C 60 °C
XBridge BEH Phenyl 80 °C 60 °C
XBridge BEH Shield RP18 50 °C 45 °C
XBridge BEH HILIC 45 °C 45 °C
XBridge BEH Amide 90 °C 90 °C
Note: Working in combinations of extreme pH, temperature and pressure may
result in reduced column lifetime.
IV. COLUMN CLEANING, REGENERATION AND
STORAGE
a. Cleaning and Regeneration
Changes in peak shape, peak splitting, shouldering peaks, shifts
in retention, change in resolution or increasing backpressure may
indicate contamination of the column. Flush with a neat organic
solvent to remove the non-polar contaminant(s), taking care not to
precipitate any buffered mobile-phase components. If this flushing
procedure does not solve the problem, purge the column with the
following cleaning and regeneration procedures.
Use a cleaning routine that matches the properties of the samples,
stationary-phase type (reversed-phase, normal-phase or HILIC) and
will solubilize the suspected contaminate. Flush with 20 column
volumes of solvent at an intermediate temperature of 45°C. Return to
the initial mobile-phase conditions by reversing the sequence.
If using a reversed-phase column, purge the column with a sequence
of progressively more non-polar solvents (i.e., water–tomethanol–
to–tetrahydrofuran–to–methylene chloride).
If using a HILIC column, purge the column with a sequence of progres-
sively more polar-organic solvents (i.e., acetonitrile-to-acetonitrile/
methanol-to-acetonitrile/water-to-water).
If column performance has not improved after regeneration/cleaning pro-
cedures, contact your local Waters representative for additional support.
b. Storage after Reversed-Phase Use
For periods longer than four days, store the XP 2.5 µm Column in
100% acetonitrile. For separations utilizing elevated temperature,
store immediately after use in 100% acetonitrile. Do not store
columns in buffered eluents. If the mobile-phase contained a buffer
salt, flush the column with 10 column volumes of HPLC grade water
(see Table 3 for column volume information) followed by 10 column
volumes of acetonitrile. Failure to perform this intermediate step
could result in precipitation of the buffer salt in the column when
100% acetonitrile is introduced. Completely seal the column to avoid
solvent evaporation and drying out of the chromatographic bed.
Note: If a column has been run with a formate-containing mobile-phase (e.g.,
ammonium formate, formic acid, etc.) and is purged with 100% acetonitrile,
slightly longer equilibration times may be necessary when the column is re-
installed and re-wetted with that same formate-containing mobile-phase.
c. Storage after HILIC Use
For periods longer than four days, store the XP 2.5 µm Column in
95/5 acetonitrile/water. Do not store columns in buffered eluents.
If the mobile-phase contained a buffer salt, flush the column with
10 column volumes of HPLC grade water (see Table 3 for column
volume information) followed by 10 column volumes of 95/5