WPI APOLLO 4000, Instruction Manual

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APOLLO 4000
HYDROGEN PEROXIDE DETECTION
World Precision instruments e-3
note: the calibration should be carried out at the temperature at which the
samples of H
o are to be measured. this can be accomplished by placing the
vial and stand in a water bath at the appropriate temperature, and allowing the
temperature of the solution in the bottle to equilibrate with the water bath.
5. once the current has achieved a stable value. it is ready for calibration.
Creating a calibration curve
to create a calibration curve, the user measures
the current (pA) generated by the addition of
different amounts of H
o to the calibration
solution.
1. After the current is stable, zero the baseline.
2. Add a known volume of the H o standard
solution to the PBs buffer solution.
For example, add 0, 5, 0, 0, 40, 80ml H o
standard solution (.0mm) into 0ml PBs buffer solution.
the output from the H o will like similar to the example shown in Fig. E1 .
From this output, a calibration curve ( Fig. E2 ) can
be created by plotting the changes in current (pA)
against the changes in concentration (mm). the
slope of this curve indicates sensitivity of the probe.
-100
100
300
500
700
900
1100
1300
-30 20 70 120 170
time (sec)
current (pA)
0.5
µ
M
1
µ
M
2
µ
M
4 µ M
8
µ
M
Figure E1
— H
2
O
2
calibration
output.
y = 73.296x + 6.4857
R
2
= 0.9988
0
100
200
300
400
500
600
700
0 2 4 6 8 10
Concentration of H
2
O
2
(
µ
M)
Current (pA)
Figure E2
—
ISO-HPO-2
calibration curve
based on Figure 1