Thermo Scientific™

DyLight™ 550-2xPEG NHS Ester

Catalog number:  62269

 Related applications:

Protein Labeling & Crosslinking

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Thermo Scientific DyLight 550-2xPEG Amine-Reactive Dye is a derivative of our high-performance DyLight 550 Dye that can be used to fluorescently label antibodies and other proteins.

The DyLight 550-2xPEG dye contains 2 polyethylene glycol (PEG) chains that are non-cytotoxic, enhance fluorescence, and reduce nonspecific binding of conjugates made with them. Conjugates made with DyLight 550-2xPEG Dye can be used as molecular probes for cellular imaging, flow cytometry, and other fluorescence detection methods. The PEG chains also improve solubility of the dyes and labeled molecules in aqueous solution, aid in cell permeability, and improve tissue retention.

Features of DyLight 550-2xPEG NHS Ester:

High fluorescence intensity—significantly brighter fluorescence than Alexa Fluor™ 555
PEGylated—improves solubility in aqueous solution and aids in cell permeability

• Fluorescence microscopy
In vivo or ex vivo imaging
• Cell-based assays
• Flow cytometry/fluorescence-activated cell sorting (FACS)

DyLight 550-2xPEG Amine-Reactive Dye is activated with an N-hydroxysuccinimide (NHS) ester moiety to react with exposed N-terminal α-amino groups or the ε-amino groups of lysine residues to form stable amide bonds. Learn more about NHS ester chemistry.

Typical labeling reactions require the dye to first be dissolved in anhydrous dimethyl formamide (DMF) or another suitable organic solvent before adding a specific molar amount of dye to an amine-free buffer containing the protein to be labeled. However, the high solubility of DyLight Fluors permits protein solutions to be added directly to the labeling reagent.
For Research Use Only. Not for use in diagnostic procedures.


Label or Dye: DyLight™ 550
Chemical Reactivity: Amine
Excitation⁄Emission (nm): 562⁄576
Product Line: DyLight™
Product Size: 1 mg
Solubility: DMF (Dimethylformamide)

Contents & storage

Store desiccated at -20°C.


Manuals & protocols