663625-18-1

Rhod-2 (potassium salt) is a water-soluble, red fluorescent calcium indicator. It exhibits a significant shift in fluorescence intensity upon calcium binding (ex max = 549 nm; calcium-free v. ex/em max = 552/581 nm; calcium-bound).^1,2 Unlike the UV-excitable indicators fura-2 and indo-1 , there is no accompanying spectral shift.

1. Paredes, R.M., Etzler, J.C., Watts, L.T., et al. Chemical calcium indicators Methods 46(3),143-151(2008).
2. Minta, A., Kao, J.P., and Tsien, R.Y. Fluorescent indicators for cytosolic calcium based on rhodamine and fluorescein chromophores J. Biol. Chem. 264(14),8171-8178(1989).