rhod ff (potassium salt)

Rhod-FF is a difluorinated analog of the cell-impermeant calcium indicator rhod-2. It has a very low affinity for calcium (Kd = 320 μM). Low affinity calcium indicators are particularly useful for studying compartments with high concentrations of calcium, such as endoplasmic reticulum, where high affinity dyes will be insensitive to luminal fluctuations. Rhod-FF has excitation emission maxima of approximately 552 and 580 nm, respectively.