AZDye 488 Maleimide

Unit Size
Price (USD)
Cat.#: 1014-1
Unit size: 1 mg
in stock
Cat.#: 1014-5
Unit size: 5 mg
in stock
Cat.#: 1014-25
Unit size: 25 mg
in stock
Cat.#: 1014-100
Unit size: 100 mg
in stock

AZDye™ 488 (Alexa Fluor® 488 equivalent) is a green-fluorescent, water-soluble dye with pH insensitive emission from pH 4 to pH 10. This dye is ideally suited to the 488 nm laser line. AZDye 488 is one of the brightest dyes commercially available with fluorescence quantum yield close to 100%.

Maleimide is the most popular sulfhydryl-reactive reactive group for conjugating the dye to either a thiol group on a protein, oligonucleotide thiophosphate, or low molecular weight ligand. The maleimide group specifically and efficiently reacts with reduced thiols (sulfhydryl groups, –SH) at pH 6.5 to 7.5 to form stable thioether bonds. The resulting conjugates exhibit brighter fluorescence and greater photostability than the conjugates of many other spectrally similar fluorophores.

AZDye™ 488 Maleimide dye is structurally identical to Alexa Fluor® 488 C5 Maleimide dye.

Thiol (Cys)
Abs/Em Maxima
493/516 nm
Extinction coefficient
72,000 cm-1M-1
Water, DMSO, DMF
Spectrally similar dyes
Alexa Fluor® 488, DyLight® 488, Fluorescein, Oregon Green 488
Molecular weight
698.67 (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® is a registered trademark of Thermo Fisher Scientific.