IR 680LT NHS ester

Unit Size
Price (USD)
Cat.#: 1526-1
Unit size: 1 mg
in stock
Cat.#: 1526-5
Unit size: 5 mg
in stock
Cat.#: 1526-25
Unit size: 25 mg
in stock
Cat.#: 1526-100
Unit size: 100 mg
in stock

IR 680LT (IRDye® 680LT equivalent) is a bright, water-soluble dye that is structurally very similar to the commonly used Cy®5.5 Dye. The water solubility, brightness, and self-quenching characteristics of this dye were significantly improved by the introduction of two additional sulfo groups. Far-red fluorescent IR 680 conjugates are spectrally similar to other 680 nm dyes that are used for flow cytometry, microscopy and other applications. Proteins can be labeled with IR 680 at high molar ratios without significant self - quenching, leading to brighter conjugates and more sensitive detection.

The NHS ester (succinimidyl ester) is the most popular tool for conjugating this dye to a protein or antibody. NHS esters can be used to label to the primary amines of proteins (Lys), amine-modified oligonucleotides, and other amine-containing molecules.

Primary amine
Abs/Em Maxima
679/694 nm
Extinction coefficient
190,000 cm-1M-1
Water, DMSO, DMF
Spectrally similar dyes
Alexa Fluor® 680, DyLight® 680, IRDye® 680
Molecular weight
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

IRDye® is a trademark of LI-COR Biotechnology.