DyLight™ 550 Maleimide

Thermo Scientific DyLight 550 Sulfhydryl-Reactive Dye is a maleimide-activated derivative of high-performance DyLight 550 used to fluorescently label sulfhydryl-containing peptides, proteins and other biomolecular probes.

DyLight 550 provides vibrant orange-to-red fluorescence with better performance than other rhodamine derivatives including Alexa Fluor™ 555, TRITC and Cy3™ dye for fluorescent applications over a broad pH range (pH 4-9). The high water solubility of DyLight Fluors means that a high dye-to-protein ratio can be attained without causing precipitation of the conjugates.

Features of DyLight 550 Maleimide:

• High performance—DyLight 550 shows brighter fluorescence than Alexa Fluor 555, TRITC and Cy3 dye
• Specific—maleimide-activated dye labels proteins and other molecules at reduced sulfhydryls (-SH)
• Efficient labeling methods—well-characterized chemistry and optimized protocols provide for reliable, high-quality labeling
• Optimized antibody labeling procedure—complete protocol for IgG reduction and labeling and calculating the labeling efficiency

Applications:
• Antibody labeling for immunofluorescence applications, including immunocytochemistry (ICC), immunohistochemistry (IHC), Western blotting and ELISA assay
• Target macromolecule labeling for in vitro and in vivo fluorescent detection strategies

DyLight 550 Sulfhydryl-Reactive Dye is activated with a maleic acid imide (maleimide) moiety to form a reactive alkylation reagent. Labeling occurs through reaction of the maleimide-activated dye with reduced sulfhydryl groups (-SH) to form stable thioether bonds. Maleimides are specific for sulfhydryl groups between pH 6.5-7.5. Learn more about maleimide chemistry.