Waters XSelect CSH XP 2.5 µm Columns - Manual (Page 5)

XSelect CSH XP 2.5 µm Columns 5
[ CARE AND USE MANUAL ]
3. Orient the XP 2.5 µm Column perpendicular to the work surface
so that the column inlet is on the bottom.
4. From below, insert the VanGuard Pre-Column into the column
inlet; turn the assembled column and pre-column 180° so that
the pre-column is now on top.
5. Tighten with two 5/16” wrenches placed onto the XP 2.5 µm
Column flats and VanGuard Pre-Column hex nut (male end) as
shown in Figure 4.
6. While keeping pressure on the VanGuard Pre-Column against the
XP 2.5 µm Column, tighten turn to set the collet and ferrule.
7. Check that the ferrule is set by loosening the connection and
inspecting the ferrule depth.
8. Reattach the pre-column to the XP 2.5 µm Column, apply flow
and inspect for leaks.
III. COLUMN USE
To ensure the continued high performance of XSelect CSH XP 2.5 µm
Columns, follow these guidelines:
a. Sample Preparation
1. Sample impurities and/or particulates often contribute to column
contamination. One option to avoid column contamination is
to use Waters Oasis
® or Sep-Pak ® Solid-Phase Extraction (SPE)
devices. To select the appropriate sorbent for a specific sample
type, visit www.waters.com/sampleprep
2. It is preferable to prepare the sample in the initial mobile-
phase conditions or a weaker solvent for the best peak shape
and sensitivity.
3. If the sample is not prepared in the mobile phase, ensure that
the sample, solvent and mobile phases are miscible in order to
avoid sample and/or buffer precipitation.
4. Filter sample with a 0.2 µm membrane to remove particulates.
If the sample is dissolved in a solvent that contains an
organic modifier (i.e., acetonitrile, methanol) ensure that the
membrane/filter material is compatible with the solvents in use.
Alternatively, centrifuge the sample for 20 minutes at
8000 rpm, followed by the transfer of the supernatant to an
appropriate vial could be considered.
b. pH Range
Table 4: Recommended pH Range
Chemistry pH Range
XSelect CSH C
18
1 - 11
XSelect CSH Phenyl-Hexyl 1 - 11
XSelect CSH Fluoro-Phenyl 1 - 8
Column lifetime will vary depending on the combination of
temperature, mobile-phase pH and type of buffer/additive used.
Table 5 lists the recommended buffers and additives for XSelect
CSH XP 2.5 µm Columns.
Note: Working in combinations of extreme pH, temperature and pressure may
result in reduced column lifetime.