JC-1 (I2), 5mg

A lipophilic carbocyanine fluorescent probe supplied by STEMCELL Technologies for the ratiometric assessment of mitochondrial membrane potential (ΔΨm) in living cells. JC-1 accumulates within negatively polarized mitochondria and forms red-orange aggregates (excitation ~561 nm, emission ~590 nm), while depolarized mitochondria retain the dye as green-emitting monomers (excitation ~488 nm, emission ~525 nm). The 5 mg lyophilized aliquot is reconstituted in anhydrous DMSO to produce a stock solution of approximately 1 to 5 mg/mL, then diluted into assay buffer to achieve final loading concentrations of 2 to 10 µM for 15 to 45 minutes at 37 °C. Researchers apply the probe in flow cytometry, fluorescence microscopy, and microplate fluorometry to interrogate apoptosis, mitophagy, mitochondrial bioenergetics, and cardiotoxicity screening. Store the vial sealed and protected from light at 2 to 8 °C, and limit repeated freeze-thaw cycles by preparing single-use aliquots in DMSO. The intensity ratio of red to green fluorescence provides a quantitative readout of mitochondrial health across mammalian cell models, primary cultures, and differentiating stem cell populations.