AZDye 555 NHS ester

Unit Size
Price (USD)
Cat.#: 1166-1
Unit size: 1 mg
in stock
Cat.#: 1166-5
Unit size: 5 mg
in stock
Cat.#: 1166-25
Unit size: 25 mg
in stock
Cat.#: 1166-100
Unit size: 100 mg
in stock

AZDye™ 555 NHS Ester is a water-soluble, bright orange-fluorescent dye with excitation ideally suited for the 532 nm or 555 nm laser lines and visualized with TRITC (tetramethylrhodamine) filter sets. AZDye™ 555 conjugates of antibodies, peptides, and proteins are pH insensitive from pH 4 to pH 10. Proteins can be labeled with AZDye 555 NHS Ester at high molar ratios without significant self-quenching, leading to brighter conjugates and more sensitive detection. AZDye™ 555 conjugates ideally suited for detection of low abundance targets.

The NHS Ester reacts specifically and efficiently with a primary amine at pH 7-9 to form a stable, covalent amide bond. The NHS ester (or succinimidyl ester) is the most popular tool for conjugating dyes to the primary amines of protein or antibody (Lys), amine-modified oligonucleotides, and other amine-containing molecules.

Primary amine
Abs/Em Maxima
555/572 nm
Extinction coefficient
155,000 cm-1M-1
Water, DMSO, DMF
Spectrally similar dyes
Cy3, DyLight® 550, Alexa Fluor® 555
Molecular weight
930.04 (protonated)
Storage conditions
Shipping conditions
Ambient temperature


Enter only one — either volume or amount of protein to be labeled
Enter only one — either maximum concentration of DMSO or volume DMSO added to label

Alexa Fluor® Dyes is a registered trademark of Thermo Fisher Scientific.