Rhodamine 123, similar with TMRE and TMRM, is a fluorescent lipophilic cation which can accumulate rapidly and reversibly in the mitochondria of living cells due to the negative Δψ_m of the mitochondria.

Store in dark at 4 ℃.

1. Prepare a stock solution of Rhodamine 123 at 1 mg/mL in ddH₂O, protect from light, and store at 4˚C in a sealed vial. 2. Prepare PBS with 1 mM CaCl₂ and MgCl₂. 3. Prepare a 10 µg/mL Rhodamine-123-labeling solution in PBS just before staining. 4. Aspirate the culture medium from cells grown on coverslips, and wash the cells three times with PBS. 5. Incubate the cells in the Rhodamine-labeling solution for 15 min at 37˚ in dark. 6. Aspirate the labeling solution, and rinse the cells three times in PBS. 7. Mount the coverslips. 8. Image the cells.{{Chazotte B. Labeling mitochondria with rhodamine 123. Cold Spring Harb Protoc. 2011 Jul 1;2011(7):892-4. doi: 10.1101/pdb.prot5640. PMID: 21724815.|https://pubmed.ncbi.nlm.nih.gov/21724815/}} For Rhodamine 123, λ_ex ~504 nm; λ_em 534 nm. Maxima may vary somewhat depending on the concentration of the dye in the mitochondrion and especially in different solvents. Isolated, energized mitochon

Rhodamine 123, similar with TMRE and TMRM, is a fluorescent lipophilic cation which can accumulate rapidly and reversibly in the mitochondria of living cells due to the negative Δψ_m of the mitochondria. It emits a green fluorescence with a maximum at 529 nm when excited at 507nm. Thus, it is used to monitor the membrane potential of mitochondria. Rhodamine 123 has excitation/emission maxima of 507/529 nm.