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CF® Dye Maleimides

CF® Dye Maleimides are thiol-reactive fluorescent dyes. Maleimides are commonly used to label proteins, peptides or other molecules containing free thiol groups.

Product Attributes

Chemical reactivity (reacts with)


Functional group


Storage Conditions

Store at -10 to -35 °C, Protect from light

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Product Description

CF® Dye Maleimides are thiol-reactive fluorescent dyes. Maleimides are commonly used to label proteins or small ligands like peptides or oligonucleotide thiophosphates on free thiol groups.

  • Thiol-reactive fluorescent dyes.
  • Stably label antibodies, proteins, or small ligands like peptides or oligonucleotide thiophosphates on free thiol groups.
  • Bright, photostable and water-soluble CF® dyes are excellent options for fluorescent labeling.

Superior CF® Dyes

CF® dyes are Biotium’s line of next-generation fluorescent dyes that have improved brightness, photostability and water solubility compared to Alexa Fluor®, DyLight®, and other fluorescent dyes.

Learn more about CF® Dyes. For more information download the CF® Dye Brochure.

ProductEx/EmSizeCatalog No.Purchase
CF®350 Maleimide347/448 nm1 umol92020Purchase 92020
CF®405S Maleimide404/431 nm1 umol92030Purchase 92030
CF®405M Maleimide408/452 nm1 umol92021Purchase 92021
CF®405L Maleimide395/545 nm1 umol92046Purchase 92046
CF®430 Maleimide426/498 nm1 umol92118Purchase 92118
CF®440 Maleimide440/515 nm1 umol92124Purchase 92124
CF®450 Maleimide450/538 nm1 umol96012Purchase 96012
CF®488A Maleimide490/515 nm1 umol92022Purchase 92022
CF®503R Maleimide503/532 nm1 umol96079Purchase 96079
CF®532 Maleimide527/558 nm1 umol92045Purchase 92045
CF®543 Maleimide541/560 nm1 umol92044Purchase 92044
CF®550R Maleimide551/577 nm1 umol96074Purchase 96074
CF®555 Maleimide555/565 nm1 umol92023Purchase 92023
CF®568 Maleimide562/583 nm1 umol92024Purchase 92024
CF®570 Maleimide568/591 nm1 umol96015Purchase 96015
CF®583 Maleimide583/606 nm1 umol96017Purchase 96017
CF®594 Maleimide593/614 nm1 umol92025Purchase 92025
CF®620R Maleimide617/639 nm1 umol92033Purchase 92033
CF®633 Maleimide630/650 nm1 umol92026Purchase 92026
CF®640R Maleimide642/662 nm1 umol92034Purchase 92034
CF®647 Maleimide650/665 nm1 umol92027Purchase 92027
CF®660C Maleimide667/685 nm1 umol92028Purchase 92028
CF®660R Maleimide663/682 nm1 umol92031Purchase 92031
CF®680 Maleimide681/698 nm1 umol92029Purchase 92029
CF®680R Maleimide680/701 nm1 umol92032Purchase 92032
CF®750 Maleimide755/777 nm0.5 umol96062Purchase 96062
CF®800 Maleimide797/816 nm0.25 umol92128Purchase 92128


1. J Gen Physiol (2014) 143 (1): 105–118. DOI: 10.1085/jgp.201311053
2. J Biol Chem (2015) 290: 17956-17966. DOI: 10.1074/jbc.M115.641688
3. Nature Methods (2015) 12:773–779. DOI: 10.1038/nmeth.3475
4. Biophys J (2018) 115:996-1006. DOI: 10.1016/j.bpj.2018.07.037

Download a list of CF® dye references.


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