Sulfo-Cyanine 5 NHS ester

A variety of cyanine dyes has been used to label biological molecules for fluorescence imaging and other fluorescence-based biochemical analysis. They are widely used for labeling peptides, proteins and oligos etc. Cy5® dyes are one type of the most common red fluorophores. These versatile fluorophores can tolerate a pH range of 3-10 for use in a variety of applications at biologically relevant pHs. The dyes are also DMSO tolerant and photostable to enable transfer from storage to assay without loss of performance. The aqueous solubility eliminates the need for organic solvents in the assay buffers. Sulfo-Cyanine 5 is an alternative dye primarily used for labeling peptides and oligos in replacing Cy5 that was originally developed by GE Healthcare (Cy5® is the trademark of GE Healthcare). NHS ester dyes are recommended for labeling amine groups and maleimide dyes are recommended for labeling thiol groups. This Cy5® NHS ester readily reacts with amino groups.