MB 543 Maleimide

Catalog#

Unit Size

Price (USD)

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Qty

Cat.#: 1638-1

Unit size: 1 mg

$129.00

in stock

Cat.#: 1638-5

Unit size: 5 mg

$395.00

in stock

Cat.#: 1638-25

Unit size: 25 mg

$1,295.00

in stock

Cat.#: 1638-100

Unit size: 100 mg

$2,495.00

in stock

MB™ 543 is a very hydrophilic, water-soluble orange fluorescent dye. Structurally related to Alexa Fluor® 546 dye, MB™ 543 dye contains an additional, negatively charged sulfo group (SO3H) to improve water solubility and minimize self-quenching. Characteristic features of MB™ 543 are strong absorption, high fluorescence quantum yield, high photostability, and pH insensitivity from pH 3 to pH 10. MB™ 543 is a highly suitable dye for single-molecule detection applications and high-resolution microscopy such as PALM, dSTORM, STED etc.

Maleimide is the most popular sulfhydryl-reactive reactive group for conjugating the dye to 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 bond. The resulting conjugates exhibit brighter fluorescence and greater photostability than the conjugates of many other spectrally similar fluorophores.

Specifications
Structure
Abs/Em Spectra
Protein Labeling Calculator

Reactivity

Thiol (Cys)

Abs/Em Maxima

543/566 nm

Extinction coefficient

105,000 cm-1M-1

Solubility

Water, DMSO, DMF

Spectrally similar dyes

Alexa Fluor® 546, CF® 543, TAMRA

Molecular weight

941.23

Storage conditions

-20C

Shipping conditions

Ambient temperature

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