Lower O2 limit - DatLab
MitoPedia O2k and high-resolution respirometry: O2k-Open Support
A Lower O2 limit [µM] can be defined for each O2k-chamber, to trigger an automatic warning when the experimental O2 concentration drops below this limit. It reminds the user that re-oxygenation of the O2k-chamber may be required. For the lower O2 concentration limit, the critical oxygen concentration should be considered, which differs between isolated mitochondria, large cells, and permeabilized muscle fibers. A higher limit should be chosen when high oxygen flux is expected, e.g. prior to uncoupler titration. A lower limit is acceptable prior to inhibition of respiration causing low oxygen flux.
- When the oxygen concentration declines below the limit, a red flashing warning line appears to the right of every graph that displays information about the affected chamber. If for example the O2 concentration of chamber A is below the limit, the warning line does not only flash to the right of the top graph, but also to the right of the temperature graph. The flashing warning line disappears as soon as the O2 concentration is above the limit.
- In addition to the visual warning, a warning event is set in the plot. A click on the event triggers a pop-up window showing the event's name, the time, the reason for the event, the limit that was set and the O2 concentration that triggered the event.
- In DatLab 7 set the lower O2 limit in the pull-down menu 'Protocol' » Run DL-Protocol/Set O2 limit
- Lower O2 limit [µM]. When checked, an automatic warning notifies the user when the actual oxygen level falls below the specified value for the according chamber: A red flashing "WARNING" button in the status line (DatLab window bottom, right) appears and a "WARNING" event is set in the plot. To reset the actual warning status (to notify the next possible fall-below), the red flashing "WARNING" button has to be clicked. First, a 'Warning window' opens to show all warnings during the experiment. After closing the window, the reset is completed.
Click 'Protocols' in the top menu bar and select 'Set lower O2 limit' from the drop-down menu. The option is available whenever an oxygen signal is recorded. Different lower O2 limits can be chosen for each chamber. Different limits can be chosen in the course of an experiment.
MitoPedia O2k and high-resolution respirometry: DatLab