Fluorescent dye; supplied as an NHS ester for coupling to primary amine groups. Compatible with self-labeling tag systems, e.g. HaloTag? and SNAP-tag?. Suitable for confocal fluorescent imaging and super resolution microscopy (SRM) techniques, such as dSTORM (live and fixed cells) and STED. Cell permeable. Excitation maximum = 549 nm; emission maximum = 571 nm; Quantum yield = 0.88; Extinction coefficient = 101,000 M-1cm-1; A280 correction factor is 0.169. We also offer Janelia Fluor? conjugated antibodies and custom conjugation services with our sister company Novus Biologicals. HaloTag is a trademark of Promega Corporation, and SNAP-tag is a trademark of New England BioLabs, Inc.. MW (observed): 551.56.