Care and use manual – Waters ACQUITY UPC2 Trefoil Columns User Manual
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[ CARE AND USE MANUAL ]
ACQUITY UPC
2
Trefoil Columns Care & Use
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
. 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.
ACQUITY UPC
2
Trefoil Columns are designed for supercritical
(compressed CO
2
) applications. ACQUITY UPC
2
Trefoil Columns
may be used with compressed CO
2
and the following co-solvents
(individually and in miscible combinations): alcohols (typically
methanol, ethanol, isopropanol), acetonitrile and alkanes
(typically heptane and hexane). Under SFC conditions, the
co-solvent elution strength is in the following order: methanol >
ethanol > isopropanol > acetonitrile > alkanes. When dissolving
samples for analysis, use an injection solvent that is weaker
to avoid peak distortion. Employing blends of methanol,
isopropanol, acetontrile and/or heptane commonly maintains
analyte solubility while avoiding strong injection solvent
peak distortion.
Water tends to have a irreversible effect on selectivity. While not
damaging the polysaccharide, the selectivity will be permanently
effected upon exposure.
ACQUITY UPC
2
Trefoil Columns contain a modified polysaccharide
coating which can be damaged when exposed to stronger solvents.
Solvents that must be avoided include:
■
■
Ketones such as acetone, methyl ethyl ketone (MEK)
■
■
Halogenated solvents such as chloroform, dichloromethane,
methylene chloride
■
■
Ethyl acetate
■
■
Tetrahydrofuran (THF)
■
■
Methyl tert-butyl ether (MTBE)
■
■
Toluene
■
■
Dimethyl formamide
■
■
Dimethyl sulfoxide
■
■
N-Methylformamide
c. Additives
ACQUITY UPC
2
Trefoil 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