Waters ACQUITY UPC2 Torus Columns - Manual (Page 4)

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[ CARE AND USE MANUAL ]
ACQUITY UPC 2 Torus Columns Care & Use
4. From below, insert VanGuard Pre-column into ACQUITY UPC 2
Column inlet and hand-tighten (collet and ferrule are not yet
permanently attached).
5. While pushing the VanGuard Pre-column into the column inlet,
turn assembled column and pre-column 180˚ so that pre-
column is now on top.
6. Tighten with two 5/16” wrenches placed onto ACQUITY UPC 2
Column flats and VanGuard Pre-column hex nut (male end) as
shown above.
7. Tighten 1/4 turn to set collet and ferrule.
8. Check that ferrule is set by loosening connection and
inspecting the ferrule depth. A properly set ferrule depth will
resemble other connections in the ACQUITY UPC
2 System.
9. Reattach pre-column, connect VanGuard Pre-column and
analytical column combination to the ACQUITY UPC 2 System,
apply mobile-phase flow and inspect for leaks.
III. COLUMN USE
To ensure the continued high performance of ACQUITY UPC 2
Columns, follow these guidelines:
a. Sample Preparation
1. Sample impurities often contribute to column contamination.
Waters offers both solid-phase extraction (SPE) and
supercritical fluid extraction (SFE) options. For SPE, use
Oasis
® Solid-Phase Extraction Cartridges/Columns or
Sep-Pak ® Cartridges of the appropriate chemistry to cleanup
the sample before analysis. For more information, visit to
www.waters.com/sampleprep . Alternatively, Waters offers
the MV-10 ASFE Supercritical Fluid Extraction System for high
throughput extractions from a wide variety of sample matrices.
2. Consider preparing the sample in a weak solvent (such as
heptane) for the best peak shape and sensitivity. Using weak
sample diluents may avoid peak distortion due to “strong
solvent effects”. In particular, stronger solvents can impact
peak shapes of low retaining analytes.
3. If the sample is not dissolved in the mobile-phase modifier,
ensure that the sample, solvent and mobile phases are miscible
in order to avoid sample precipitation. Filter sample with
0.2 μm membranes to remove particulates. If the sample is
dissolved in a solvent, ensure that the membrane material
does not dissolve in the solvent. Contact the membrane
manufacturer with solvent compatibility questions. Acrodisc
®
filters are recommended (refer to the Waters Quality
Parts,
® Chromatography Columns and Supplies Catalog for
additional information). Please consider that some analytes
can be retained on certain membrane materials and result
in lower recovery (or lower detector signal) than expected.
Alternatively, centrifugation for 20 minutes at 8000 rpm,
followed by the transfer of the supernatant liquid to an
appropriate vial could be considered.
b. Solvents
To maintain maximum column performance, use high quality
chromatography grade solvents. Solvents containing suspended
particulate materials will generally clog the outside surface
of the inlet distribution frit of the column. This will result in
higher operating pressure, reduced column lifetime, and
compromised performance.
c. Additives
ACQUITY UPC 2 Torus Columns can safely be used with commonly
used acidic and basic additives used in supercritical fluid
chromatography (SFC) such as trifluoroacetic acid (TFA), formic
acid, ammonium acetate, ammonium formate, ammonium
hydroxide, and organic amines (such as diethylamine and
triethylamine) and ammoniated methanol. Typical concentrations
of 20 mM or 0.2% can be used safely. Consider the volatility,
solubility and detector compatibility when choosing an
appropriate additive. Additives tend to improve peak shape and
control the retention characteristics of analytes, but can also
impart different selectivities. It is recommended to flush and
remove additives and salts from the column before placing the
column into storage.
d. Pressure
ACQUITY UPC 2 Column hardware and packing materials are
packed and tested to pressures of up to 6,000 psi (414 bar or
41 Mpa).