Thermo Scientific Dionex IonPac AG31, Руководство по эксплуатации продукта

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3 – Operation
Thermo Scientific Product Manual for IonPac AS31 Columns Page 16 of 45
155007-01
For Research Use Only. Not for use in diagnostic procedures.
The Dionex ADRS 600 must be operated in the AutoSuppression External Water Mode
when using eluents containing organic solvents. Refer to the Suppressor Product Manual
(Document No. 031956) for operation limitations in the electrolytic mode (power on).
3.5 Eluent Preparation
A Dionex Eluent Generator (EG) is recommended for use with Dionex IonPac columns.
When preparing eluents manually, ensure all chemicals and water are of the highest purity.
3.5.1 Manually Prepared Eluents
Eluents should be stored in plastic bottles under a helium atmosphere to ensure contamination
free operation and proper pump performance (nitrogen can be used if eluents do not contain
solvents). Contamination from carbon dioxide when basic eluents are exposed to the air can cause
performance variability such as retention time shifts.
3.5.2 Making Eluents that Contain Solvents
Mixing solvents with water should be done on a volume to volume basis. For example, if a
procedure requires an eluent of 40% acetonitrile, prepare the eluent by adding 400 mL of
acetonitrile to an eluent reservoir. Then add 600 mL of deionized water or eluent concentrate to
the acetonitrile in the reservoir. Using this procedure to mix solvents with water will ensure that
a consistent true volume/volume eluent is obtained. Premixing water with solvent will minimize
the possibility of outgassing.
When purging or degassing eluents containing solvents, do not purge or degas the eluent
excessively since it is possible that a volatile solvent will evaporate or be “boiled” off from
the solution under reduced pressure.
Always degas and store all eluents in plastic eluent bottles pressurized with helium. Only
helium can be used to purge and degas ionic eluents containing solvents, since nitrogen is
soluble in solvent containing eluents.
Acetonitrile (ACN) hydrolyzes to ammonia and acetate when exposed to basic solutions.
To prevent eluent contamination from acetonitrile hydrolysis, always add acetonitrile to
basic aqueous eluents by proportioning the acetonitrile into the basic eluent with the
gradient pump. Keep the acetonitrile in a separate eluent bottle containing only acetonitrile
and water.
Never add the acetonitrile directly to the basic carbonate or hydroxide eluent solutions.
CAUTION
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NOTE
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NOTE
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NOTE
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SAFETY
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