5-TAMRA-PEO12 SE (full name: 5-Carboxytetramethylrhodamine-PEO12-propionate succinimidyl ester) has a long water-soluble PEG spacer between TAMRA (tetramethylrhodamine) and the amine-reactive SE group.λEx/λEm (MeOH) = 540/565 nm Dark red solid soluble in DMSO or DMF Store at -20°C and protect from light C56H78N4O20 MW: 1127.23