Different methods for measurements of mt-membrane potential
Mt-membrane potential can either be measured with the O2k-Fluo LED2-Module by using the fluorophores TMRM or Safranin or with the O2k-TPP+ ISE-Module electrode by using the ion reporter TPP+.
O2k-Fluo LED2-Module / Safranin and TMRM
This method is easy in handling since the Fluorescence-Sensor does not get in direct contact with the sample. The sensitivity of the fluorometric measurement is < 100 mV. However, test experiments show inhibition of respiration by fluorophores ##.
References:
- Krumschnabel G, Eigentler A, Fasching M, Gnaiger E (2014) Use of safranin for the assessment of mitochondrial membrane potential by high-resolution respirometry and fluorometry. Methods Enzymol 542:163-81. » Bioblast link «
- Sumbalova Z, Gnaiger E (2015) High-resolution measurement of mitochondrial membrane potential and respiration – comparison of potentiometric and fluorometric methods. Abstract MiP2015. Bioblast link
O2k-TPP+ ISE-Module / TPP+ and TPMP
The O2k-TPP+ ISE-Module is a potentiometric method for determination of the mt-membrane potential by using the ion reporter TPP+ or TPMP. This method is suitable for measurements with a sensitivity > 100 mV MiPNet15.08_TPP-Electrode#Sensitivity_analysis_of_the_method and the ## can be determined directly by ###. Using the TPP-ISE electrode requires special care after the experiment, since the electrode is inserted in the chamber and therefore gets in direct contact with the medium, substrates, uncouplers and also inhibitors. Standardized operating procedures help to avoid any carry-over.
