Thermo Scientific Dionex ICS-2000, Operator'S Manual

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1 • Introduction
Doc. 031857-03 4/06
1-3
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The pump pushes the eluent and sample through the guard and
separator columns (chemically-inert tubes packed with a polymeric
resin). The guard column removes contaminants that might poison the
separator column.
3. Separation
•
As the eluent and sample are pumped through the separator column,
the sample ions are separated. In the ICS-2000, the mode of
separation is called ion exchange. This is based on the premise that
different sample ions migrate through the IC column at different rates,
depending upon their interactions with the ion exchange sites.
4. Suppression
•
After the eluent and sample ions leave the column, they flow through
a suppressor that selectively enhances detection of the sample ions
while suppressing the conductivity of the eluent.
5. Detection
•
A conductivity cell measures the electrical conductance of the sample
ions as they emerge from the suppressor and produces a signal based
on a chemical or physical property of the analyte.
6. Data Analysis
•
The conductivity cell transmits the signal to a data collection system.
•
The data collection system (for the ICS-2000, this is Chromeleon)
identifies the ions based on retention time, and quantifies each analyte
by integrating the peak area or peak height. The data is quantitated by
comparing the sample peaks in a chromatogram to those produced
from a standard solution. The results are displayed as a chromatogram
and the concentrations of ionic analytes can be automatically
determined and tabulated.