Metrohm 940 Professional IC Vario ONE/SeS/PP/Prep 3 - Manual (Page 110)

5.17 Sample preparation module (SPM)
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100 ￭￭￭￭￭￭￭￭
940 Professional IC Vario ONE/SeS/PP/Prep 3 (2.940.1530)
The time upon stopping the watch corresponds to the "transfer
time".
If the sample is injected automatically, the rinsing time has to be at least
three times the transfer time.
Checking the rinsing time
You can determine if the applied rinsing time is sufficient by measuring
the sample carry-over directly. Proceed as follows to do this:
1 Preparing two samples
￭ Sample A: A typical sample for the application.
￭ Sample B: Ultrapure water.
2 Determining "Sample A"
Allow "Sample A" to run through the sample path for the duration of
the rinsing time; inject and then measure it.
3 Determining "Sample B"
Allow "Sample B" to run through the sample path for the duration of
the rinsing time; inject and then measure it.
4 Calculating the sample carry-over
The sample carry-over corresponds to the ratio of the peak areas of
the measurement from Sample B to the measurement from Sample
A. The smaller this ratio is, the smaller the sample carry-over. This
ratio can be changed by varying the rinsing time. This can be used to
determine the required rinsing time for the application.
5.17 Sample preparation module (SPM)
5.17.1 Notes for operating the SPM
CAUTION
The neutralization units must never be regenerated in the same flow
direction the eluent is pumped during operation. Therefore, always
mount the inlet and outlet capillaries according to the diagram outlined
in figure 3.18.2, page 50.