PH electrode
From Bioblast
Using the pH probe in the O2k to measure Proton production requires some modifications of standard protocols and in fact a certain degree of method development. Some of the encountered challenges are
- very small buffering capacity required
- determination of buffering capacity necessary to calculate real proton flux
One approach we are considering now is to use the TIP to run in a "pH stat"mode, i.e. keeping the pH constant by a feedback controlled automatic injection of base, then determining proton flow from the amount of base injected. This circumvents the determination of buffering capacity. The "pH-Stat" approach might also make buffering obsolete. Alternately, the proton flow can be determined by
- injecting acid into the medium (without any biological sample) thereby determining the buffering capacity,
- running your experiment
- converting the logarithmic change in pH to a linearized Proton concentrations
- considering the buffering capacity determined before.
