Cyanine 644-cAMP is a fluorescently labeled cAMP analog and can be used to probe cAMP receptors. Single molecules of fluorescently labeled cAMP have been imaged as the probe binds to the receptor on the surface of Dictyostelium cells.     λEx/λEm (MeOH) = 644/670 nm   Dark solid soluble in H2O, DMF or DMSO   Store desiccated at -20°C and protect from light   C50H61N9O12PS   MW: 1043.11