7 injection valve, 1 protection, 8 inline sample preparation – Metrohm 882 Compact IC plus – Anion User Manual
Page 79: 9 rinsing the sample path, Injection valve, Protection, Inline sample preparation, Rinsing the sample path
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5 Handling and maintenance
882 Compact IC plus – Anion
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69
5.7
Injection valve
5.7.1
Protection
To prevent contamination of the injection valve, a 6.2821.120 inline filter
(see Chapter 3.10, page 32) should be mounted between the high pres-
sure pump and the pulsation damper.
5.8
Inline sample preparation
To protect the separation column (see Chapter 3.17, page 47) against for-
eign particles which can affect the separating efficiency, we recommend
that all samples undergo a microfiltration (filter 0.45 µm). The ultrafiltra-
tion cell can be used for filtration (see manual of the IC Equipment for
Ultrafiltration).
Matrix-loaded samples (e.g. blood, oil) should be prepared for the meas-
urement by means of dialysis (see manual on the IC Equipment for Dialy-
sis).
If the concentration of the sample is too high, the sample should be dilu-
ted before feeding (see documentation on the IC Equipment for Sample
Dilution).
For an overview of all Metrohm inline sample preparation methods go to
5.9
Rinsing the sample path
Before a new sample can be measured, the sample path must be rinsed
with it so that the measuring result is not falsified by the previous sample
(Sample carry-over).
In the case of automated sample feeding, the rinsing time should be at
least 3 times the transfer time.
The transfer time is the time required by the sample to flow from the sam-
ple vessel to the end of the sample loop. ##NO_MATCH##.
Ascertaining the transfer time
To ascertain the transfer time, proceed as follows:
1 Emptying the sample path
Pump air through the sample path (pump tubing, tubing connec-
tions, sample loop) for several minutes until all liquid is displaced by
the air.