Thermo Scientific Dionex ICS-5000, Operator'S Manual

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Dionex ICS-5000 Operator’s Manual
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Doc. 065342-06 12/11
The ED cell can be used in either capillary IC or analytical IC systems. When
used in a capillary IC system, the inlet tubing is made of PEEK. When used in
an analytical IC system, the inlet tubing is made of titanium (see
Figure 2-30 ).
Cell Design
The ED cell is a thin-layer design. Eluent flows in a thin channel parallel to
the surface of a flat disk electrode. The resulting smooth flow minimizes
noise. The low volume (<0.2

L) of the channel also allows operation with
high efficiency, narrow bore columns, and capillary columns. The cell design
minimizes the electrical resistance between the working electrode and the
counter electrode by positioning the counter electrode (the cell body) directly
across the thin-layer channel from the working electrode. This results in a
wide linear dynamic range. The inlet tubing is in electrical contact with the
counter electrode and through it to ground. The working electrode current is
processed using low noise analog amplifiers and filters.
ED Cell Solvent Compatibility
The ED cell can be used with common reversed-phase solvents such as
methanol and acetonitrile. If a disposable working electrode on polyester
substrate is used, the percentage of methanol should not exceed 30% and the
percentage of acetonitrile should not exceed 10%. In addition, prolonged
exposure (more than 8 hours) of disposable gold electrodes on polyester
substrate to eluents containing hydroxide concentrations greater than 100 mM
is not recommended. Shorter rinse periods of 10 to 20 minutes (for example,
Figure 2-30. ED Cell with pH-Ag/AgCl Reference Electrode
(Cell Configured for Analytical IC Shown)
Working
Electrode
Cell Body
(counter
electrode)
pH-Ag/AgCl
Reference
Electrode
1
2
3
1
2
3
4
4
Titanium Inlet
Tubing (for
analytical IC)