Owner manual

7.7 Standard operating procedure in the context of GLP/ISO 9001 guidelines
746 VA Trace Analyzer / 747 VA Stand
7-61
7.7.4 Performing the determination
To perform the lead determination in the prepared sample solution, the following
steps are necessary:
1
Switch to dialog page ”MONITORING”
• Press the yellow <MONITORING> key.
2
Switching the program run mode to determination
If the parameter Run mode is set to calibration, proceed as follows
• Use the cursor keys to select the field Run mode.
• Press the <CLEAR> key.
• Press the softkey <determ.> and confirm this entry with the <ENTER>
key.
3
Entry of the sample volume
Enter the sample volume as follows:
• Use the cursor keys to select the first field below the title Sample size/S0.
• Press the <CLEAR> key.
• Enter 0.1 mL and confirm this entry with the <ENTER> key.
4
Start the determination
• Press the red <START> key.
• The sample solution is measured three times. On completion of the third
measurement, the program is interrupted. The screen shows the prompt
to add 50 µL of the standard addition solution PbStd to the measuring
vessel ADD PbStd 50.000 uL > M.
5
First standard addition
• Remove stopper 2525 and add 50 µL of the lead ion standard solution to
the measuring vessel through the pipetting opening using a pipette. Then
close the pipetting opening with stopper 2525 and press the <ENTER>
key.
• The spiked sample solution is measured three times. On completion of
the third measurement, the program is interrupted. The screen again
shows the prompt to add 50 µL of standard addition solution PbStd to
the measuring vessel ADD PbStd 50.000 uL > M.
6
Second standard addition
• Remove stopper 2525 and add 50 µL of the lead ion standard solution to
the measuring vessel through the pipetting opening using a pipette. Then
close the pipetting opening with stopper 2525 and press the <ENTER>
key.
• The sample solution spiked a second time is measured three times. On
completion of the third measurement, the results are calculated and the
reports and curves printed out (see section 4.2).