The present invention discloses a new class of calcium specific fluorescent indicator dyes having visible excitation and emission wavelengths. The new fluorescent indicator dyes combine at least one tricyclic chromophore with a tetracarboxylate parent CA.sup.2+ chelating compound having the octacoordinate...http://www.google.de/patents/US5049673?utm_source=gb-gplus-sharePatent US5049673 - Fluorescent indicator dyes for calcium working at long wavelengths
