TMRM

high-resolution terminology - matching measurements at high-resolution

TMRM

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 cation that is accumulated by mitochondria in proportion to Δψ_mt. 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):

1. Weight 2.5 mg of TMRM and dissolve in 1 mL DMSO;
2. Divide into 0.2 mL portions (use dark vials);
3. Store at -20 °C.

Preparation of 1 mM solution - use for experiment:

1. Dilute a 200 µL aliquot with 800 µL DMSO to reach 1 mL final volume;
2. Divide into 0.2 mL portions (use dark vials);
3. Store at -20 °C.

Signal and output

1. 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.
2. 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