Amine-reactive form of single isomer carboxyrhodamine 110, useful in DNA sequencing. For many single-dye-labeling applications, the dye is preferred over other green fluorescent dyes including fluorescein and Alexa 488 because of its exceptional photostability and fluorescence insensitivity to pH (4-9). &lamba;Ex/&lamba; Em(MeOH) = 502/524 nm Orange red solid soluble in DMF or DMSO Store at -20°C and protect from light C33H36N4O7 MW: 600.67