Reference Measurements; Co Reference Measuring; Concentration Indirectly Via The Ph Of The Cell Medium - Binder APT.line C 150 Operating Manual

12.

Reference measurements

You can take reference measurements of the temperature and CO
located the inner glass door. Reference temperature measurements always take place under equilibrated
conditions with both doors closed.
12.1 CO reference measuring
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There are three possibilities to perform CO
tenance procedures. To test the CO
12.1.1 Measuring CO
By using the indirect determination of CO
check the CO concentration inside the chamber. This is a simple method to test the correct CO
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tration without any special CO
pH-measuring electrode, which are standard equipment in cell culture laboratories.
This method is not suitable for calibrating the BINDER FPI sensor system.
This method is based on the acid base equilibrium of the buffer system in the culture media.
NaHCO buffers the common media. From the pH value of the medium, it is possible to conclude its CO
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concentration. Figure 27 shows the relationship between CO
ferent NaHCO buffered media.
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Recommended procedure:
• Incubate an empty sample with medium for 1/2 day under the same conditions as the cells. You can
perform the incubation in a cell culture bottle or in a 50 ml Falcon tube with open lid.
• After gassing, remove the empty sample from the incubator and within 5 minutes measure the pH-
value with a glass electrode.
During the measurement, the medium should have the least possible surface contact with the ambient
air, so that the CO can evaporate only slightly. A significant downward movement will happen only af-
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ter 5 minutes, permitting sufficient time for measurement.
• In addition, you can of course use pH-test strips (pH range 6 to 8, not bleeding).
Vol.% CO
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18
16
14
2,20
12
10
1,20 g/l NaHCO
8
6
4
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6.8 7.0
Figure 27: Value pH of NaHCO
C 150 (E2) 06/2011
test measurements between the recommended annual main-
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concentration inside an incubator, see chapters 12.1.1 to 12.1.3.
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concentration indirectly via the pH of the cell medium

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concentration via the pH-value of the nutrient, it is possible to
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measuring equipment. You need only use an accurate pH indicator or a
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3,70 g/l NaHCO
3
g/l NaHCO
3
3
0,85 g/l NaHCO
3
0,35 g/l NaHCO
3
7.2
buffered media as a function of the CO
3
via the silicone measuring port (8)
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concentration in vol.-% and the pH of dif-
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Trade names of common media:
DMEM
BME
MEM
Medium 199
Mc Coy
F10
F12
7.6
7.4
Value pH
concen-
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NaHCO [g/l]
3
3.70
2.20
2.20
2.20
2.20
1.20
1.20
concentration:
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