Description
TMRM ( tetramethylrhodamine methyl ester) is an extrinsic fluorophore and can be used as a probe to determine changes in mitochondrial membrane potential. TMRM is a lipophilic cations that is accumulated by mitochondria in proportion to Δψmt. Upon accumulation of the dye it exhibits a red shift in its absorption and fluorescence emission spectrum. The fluorescence intensity is quenched when the dye is accumulated by mitochondria.
Abbreviation: TMRM
Reference: Ehrenberg 1988 Biophys J
MitoPedia methods:
Fluorometry
Application in HRFR
- TMRM: Tetramethyrhodamine methyl ester perchlorite (C25H25CIN2O7);
- Sigma T 5428 or ThermoFischer T 668, 25 mg, store at -20°C; FW = 500.93
Caution: Light sensitive (store solution in a dark vial)!
- Preparation of 5 mM stock solution (dissolved in DMSO):
- Weight 2.5 mg of TMRM and dissolve in 1 mL DMSO;
- Divide into 0.2 mL portions (use dark vials);
- Store at -20 °C.
- Preparation of 5 mM stock solution (dissolved in DMSO):
- Preparation of 1 mM solution - use for experiment:
- Dilute a 200 µL aliquot with 800 µL DMSO to reach 1 mL final volume;
- Divide into 0.2 mL portions (use dark vials);
- Store at -20 °C.
- Preparation of 1 mM solution - use for experiment:
Signal and output
- Signal: The O2k-Fluo LED2-Module is operated through the Amperometric (Amp)-Channel of the O2k, with electric current (ampere [A]) as the primary signal.
- Output: The focus of the output with TMRM is on Type C: Force, mt-membrane potential.
The TMRM method can be used with the O2k-Fluo LED2-Module. For examples of the use of TMRM with mouse liver mitochondria, rat liver tissue homogenate, and permeabilized HEK 293T cells see the discussion page of this entry