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Reactive Dyes & Biotin

CF® dyes, other dyes & biotin

Biotium offers our bright & photostable CF® dyes, other dyes, and biotin with a full selection of reactive chemistries.
Jump to a section below to learn more:

Amine-reactive NHS esters & labeling kits
Thiol-reactive dyes & thiol modifying reagents
For labeling carbonyl groups or carbohydrates
Aldehyde-reactive dyes
Azides, alkynes, BCN, tetrazine, & TCO
Tyramide dyes & TSA Signal Amplification Kits
Dye free acids & polar tracers
Reactive biotins and other biotin compounds
CF® Dye Spectrum:
CF®350 Dye

CF®350 is a blue fluorescent dye

300400500600700800900Wavelength (nm)CF350
Technical Summary

Abs/Em Maxima: 347/448 nm
Extinction coefficient: 18,000
Molecular weight: ~ 496
Excitation source: UV
Replaces: Alexa Fluor® 350, AMCA,
DyLight® 350

Features

Brighter and more photostable than AMCA
Direct replacement for Alexa Fluor® 350
Highly water soluble and pH-insensitive

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CF®405S Dye

Improved brightness & photostability for the 405 nm laser line

300400500600700800900Wavelength (nm)CF405S
Technical Summary

Abs/Em Maxima: 404/431 nm
Extinction coefficient: 33,000
Molecular weight: ~ 1,169
Excitation laser line: 405 nm
Replaces: Alexa Fluor® 405, Cascade Blue®,
DyLight® 405

Features

Brighter than Alexa Flour®  408

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CF®405M Dye

Improved brightness & photostability for the 405 nm laser line

300400500600700800900Wavelength (nm)CF405M
Technical Summary

Abs/Em Maxima: 408/452 nm
Extinction coefficient: 41,000
Molecular weight: ~ 503
Excitation laser line: 405 nm
Replaces: Pacific Blue®, BD Horizon™ V450

Features

More photostable than Pacific Blue®, with less spill-over in the green channel
An excellent choice for super-resolution imaging by SIM

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CF®405L Dye

A 405 nm-excitable dye with orange fluorescence emission

300400500600700800900Wavelength (nm)CF405L
Technical Summary

Abs/Em Maxima: 395/545 nm
Extinction coefficient: 24,000
Molecular weight: ~1573
Excitation laser line: 405 nm
Replaces: Pacific Orange®

Features
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CF®430 & CF®440 Dyes

Photostable 405 nm-excitable dyes with green fluorescence

300400500600700800900Wavelength (nm)CF430CF440
Technical Summary

CF®430
Abs/Em Maxima: 426/498 nm
Extinction coefficient: 40,000
Molecular weight: ~429
Excitation laser line: 405 nm
Replaces: Pacific Green®, BD Horizon™ V500,
Krome Orange™
CF®440
Abs/Em Maxima: 440/515 nm
Extinction coefficient: 40,000
Molecular weight: ~716
Excitation laser line: 405 nm
Replaces: Alexa Fluor® 430

Features

Photostable dyes suitable for microscopy
Perfect match for the CFP filter set
Suitable for flow cytometry in the AmCyan channel
Highly water soluble and pH-insensitive

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CF®450 Dye

A green fluorescent dye with unique spectral properties

300400500600700800900Wavelength (nm)CF450
Technical Summary

Abs/Em Maxima: 450/538 nm
Extinction coefficient: 40,000
Molecular weight: ~689
Excitation laser line: 405 nm

Features
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CF®488A Dye

A superior green fluorescent dye

300400500600700800900Wavelength (nm)CF488A
Technical Summary

Abs/Em Maxima: 490/515 nm
Extinction coefficient: 70,000
Molecular weight: ~914
Excitation laser line: 488 nm
Replaces: Alexa Fluor® 488, DyLight® 488,
fluorescein (aka FITC, FAM), Cy®2

Features

Minimally charged, for less non-specific binding than Alexa Fluor® 488
Narrower emission spectrum for less bleed to red
Very photostable
Compatible with super-resolution imaging by TIRF
Highly water soluble and pH-insensitive

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CF®514 Dye

Alternative green fluorescent dye

300400500600700800900Wavelength (nm)CF514
Technical Summary

Abs/Em Maxima: 516/548 nm
Extinction coefficient: 105,000
Molecular weight: ~1216
Excitation laser line: 488 nm
Replaces: Alexa Fluor® 514

Features

Image using the same settings as FITC or CF®488A
Can be distinguished from CF®488A in the same specimen by spectral imaging and linear unmixing

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CF®532 Dye

A bright orange fluorescent dye for the 532 nm laser

300400500600700800900Wavelength (nm)CF532
Technical Summary

Abs/Em Maxima: 527/558 nm
Extinction coefficient: 96,000
Molecular weight: ~ 685
Excitation laser line: 532 nm
Direct replacement for: Alexa Fluor® 532, Atto 532

Features

Designed for the 532 nm laser
Brighter than Alexa Fluor® 532
Highly water-soluble and pH-insensitive

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CF®535ST Dye

An orange fluorescent dye designed for STORM super-resolution imaging

300400500600700800900Wavelength (nm)CF535ST
Technical Summary

Abs/Em Maxima: 535/568 nm
Extinction coefficient: 95,000
Molecular weight: ~728
Excitation laser line: 532 nm

Features
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CF®543 Dye

An orange fluorescent dye ideal for the 543 nm laser

300400500600700800900Wavelength (nm)CF543
Technical Summary

Abs/Em Maxima: 541/560 nm
Extinction coefficient: 100,000
Molecular weight: ~ 870
Excitation laser line: 532 nm, 543 nm, or
546 nm
Direct replacement for: Alexa Fluor® 546,
TAMRA

Features

Optimized for the 543 nm laser
Yields the brightest conjugates among spectrally similar dyes
Highly water-soluble and pH-insensitive

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CF®555 Dye

A bright and photostable orange-red dye

300400500600700800900Wavelength (nm)CF555
Technical Summary

Abs/Em Maxima: 555/565 nm
Extinction coefficient: 150,000
Molecular weight: ~ 901
Excitation laser line: 532 nm or 568 nm
Direct replacement for: Alexa Fluor®
555, ATTO 550, Cy®3, DyLight® 549,
Rhodamine

Features

Brighter than Cy®3
Highly water-soluble
Validated in multicolor STORM super-resolution imaging

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CF®568 Dye

Outshines Alexa Fluor®568

300400500600700800900Wavelength (nm)CF568
Technical Summary

Abs/Em Maxima: 562/583 nm
Extinction coefficient: 100,000
Molecular weight: ~ 714
Excitation laser line: 532 nm or 568 nm
Direct replacement for: Alexa Fluor® 568,
ATTO 565, Rhodamine Red

Features

Yields much brighter antibody conjugates than Alexa
Fluor® 568
Extremely photostable
Excellent choice for multi-color imaging with CF®488A and CF®640R
Compatible with TIRF and multicolor STORM super resolution imaging

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CF®570 & CF®583 Dyes

Bright red fluorescent dyes

300400500600700800900Wavelength (nm)CF570CF583
Technical Summary

CF®570 Technical Summary

Abs/Em maxima: 568/591 nm
Extinction coefficient: 150,000
Molecular weight: ~2998
Excitation laser line: 561 to 568 nm
Replaces: Alexa Fluor® 568, ATTO 565, DY-560, Rhodamine Red

CF®583 Technical Summary

Abs/Em maxima: 583/606 nm
Extinction coefficient: 150,000
Molecular weight: ~3127
Excitation laser line: 561 to 568 nm
Replaces: Cy®3.5

Features
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CF®594 Dye

Truly the brightest deep red dye

300400500600700800900Wavelength (nm)CF594
Technical Summary

Abs/Em Maxima: 593/614 nm
Extinction coefficient: 115,000
Molecular weight: ~730
Excitation laser line: 532 nm, 568 nm or
594 nm
Replaces: Alexa Fluor® 594, DyLight® 594,
Texas Red®

Features

Yields the brightest antibody conjugates among spectrally
similar dyes.
Excellent choice for multicolor imaging with green dyes like CF®488A
Extremely photostable
Also see CF®594ST, a version of CF®594 engineered specifically for STORM microcopy

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CF®594ST Dye

Deep red dye for STORM

300400500600700800900Wavelength (nm)CF594ST
Technical Summary

Abs/Em maxima: 593/614 nm
Extinction coefficient: 115,000
Molecular weight: ~868
Excitation laser line: 532 to 568 nm

Features
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CF®620R Dye

A bright and photostable far-red dye

300400500600700800900Wavelength (nm)CF620R
Technical Summary

Abs/Em Maxima: 617/639 nm
Extinction coefficient: 115,000
Molecular weight: ~ 738
Excitation laser line: 633 nm or 635 nm
Replaces: LightCycler® Red 640

Features

Highly water-soluble
Highly fluorescent and extremely photostable
Absorption/emission at 617/639 nm for use in FRET or multi-color detection

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CF®633 Dye

The best dye for 633/635 laser lines

300400500600700800900Wavelength (nm)CF633
Technical Summary

Abs/Em Maxima: 630/650 nm
Extinction coefficient: 100,000
Molecular weight: ~820
Excitation laser line: 633 nm or 635 nm
Replaces: Alexa Fluor® 633, Alexa Fluor®
647, Cy®5, DyLight® 633, DyLight® 649

Features

Yields the brightest antibody conjugates among spectrally similar dyes
Far more photostable than Alexa Fluor® 647
Compatible with TIRF, FIONA, and gSHRImP super-resolution imaging methods

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CF®640R Dye

A highly photostable far-red dye

300400500600700800900Wavelength (nm)CF640R
Technical Summary

Abs/Em Maxima: 642/662 nm
Extinction coefficient: 105,000
Molecular weight: ~ 832
Excitation laser line: 633 nm, 635 nm or
640 nm
Replaces Alexa Fluor® 647, ATTO 647N,
Cy®5, DyLight® 649

Features

Best photostability among Cy®5-like dyes
Yields highly fluorescent protein conjugates
Compatible with TIRF and FLIMP super-resolution microscopy

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CF®647 Dye

A highly fluorescent far-red dye

300400500600700800900Wavelength (nm)CF647
Technical Summary

Abs/Em Maxima: 650/665 nm
Extinction coefficient: 240,000
Molecular weight: ~ 1058
Excitation laser line: 633 nm, 635 nm or
640 nm
Replaces: Cy®5, Alexa Fluor® 647,
DyLight® 649

Features

Brighter than Cy®5
Highly water soluble and pH insensitive
Validated in multi-color super-resolution imaging by STORM

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CF®660C and CF®660R Dyes

Superior alternatives to Alexa Fluor® 660

300400500600700800900Wavelength (nm)CF660CCF660R
Technical Summary

CF®660C
Abs/Em Maxima: 667/685 nm
Extinction coefficient: 200,000
Molecular weight: ~ 3112
Excitation laser line: 633 nm, 635 nm or 640 nm
Replaces: Alexa Fluor® 660, APC

CF®660R
Abs/Em Maxima: 663/682 nm
Extinction coefficient: 100,000
Molecular weight: ~ 888
Excitation laser line: 633 nm, 635 nm or 640 nm
Replaces: Alexa Fluor® 660, APC

Features

CF®660C Features
Much brighter and more photostable than Alexa Fluor® 660
Compatible with multicolor super-resolution imaging by STORM

CF®660R Features
Brighter than Alexa Fluor® 660
Unrivaled photostability among spectrally similar dyes

View Technology
CF®680 and CF®680R Dyes

Two outstanding 680 nm-excitable dyes

300400500600700800900Wavelength (nm)CF680CF680R
Technical Summary

CF®680
Abs/Em Maxima: 681/698 nm
Extinction coefficient: 210,000
Molecular weight: ~ 3241
Excitation laser line: 680 nm or 685 nm
Replaces: Alexa Fluor® 680, Cy®5.5, IR®Dye 680

CF®680R
Abs/Em Maxima: 680/701 nm
Extinction coefficient: 140,000
Molecular weight: ~ 912
Excitation laser line: 680 nm or 685 nm
Replaces: Alexa Fluor® 680, Cy®5.5, IR®Dye 680

Features

CF®680 Features
The brightest among spectrally similar dyes
Validated in multicolor STORM and 3D super-resolution
microscopy
Compatible with LI-COR® Odyssey®

CF®680R Features
Unrivaled photostability among spectrally similar dyes
Compatible with STED and single molecule spectroscopy super-resolution imaging (see pp. 20-21)
Molecular weight compatible with nucleic acid labeling
Compatible with LI-COR® Odyssey®

View Technology
Near-Infrared CF® Dyes

Unrivaled near-IR dyes

Technical Summary

CF®750
Abs/Em Maxima: 755/777 nm
Extinction coefficient: 250,000
Molecular weight: ~ 3009
Excitation laser line: 633, 635, 680 or 685 nm
Replaces: Alexa Fluor® 750, Cy®7, DyLight® 750

CF®770
Abs/Em Maxima: 770/797 nm
Extinction coefficient: 220,000
Molecular weight: ~ 3138
Excitation laser line: 785 nm
Replaces: DyLight™ 800, IRDye 800CW

CF®790
Abs/Em Maxima: 784/806 nm
Extinction coefficient: 210,000
Molecular weight: ~ 3267
Excitation laser line: 785 nm
Replaces: Alexa Fluor® 790

CF®800
Abs/Em Maxima: 797/816
Extinction coefficient: 210,000
Molecular weight: ~3334
Excitation laser line: 785 nm
Spectrally similar to: Indocyanine Green

Features

Exceptionally bright and stable
Ideal for in vivo imaging
Compatible with LI-COR® Odyssey®
Superior signal-to-noise for bioconjugates
Validated in STORM microscopy

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CF® Dyes for Multi-Color Super-Resolution Microscopy

Synthetic Dyes for Super-Resolution Imaging

Technical Summary
Features

CF Dyes validated in SIM, STORM, STED, TIRF, and more
Superior brightness, photostability, and photochemical switching
Single label antibody conjugates for STORM
Growing list of publications

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Amine-reactive succinimidyl esters


Succinimidyl esters (SE, also known as NHS esters) react with primary amines such as lysine residues in proteins. Succinimidyl ester labeling is commonly used for conjugation of proteins and antibodies. The reaction requires basic pH for amine groups on the target protein to be deprotonated and react with SE, and is usually performed in pH 8.3 bicarbonate buffer.

Succinimidyl ester dyes have the disadvantage of hydrolyzing over time in the presence of water. Heavily sulfonated dyes, such as the Alexa Fluor® dyes, DyLight® dyes and IRDye® are particularly hygroscopic, worsening the hydrolysis problem. In contrast, all of Biotium’s amine-reactive CF® dyes have a relatively stable form of SE, which is more resistant to hydrolysis than the SE in many of the Alexa Fluor® dyes. Accordingly, CF® dye SE products generally give consistently higher labeling efficiency, thus providing users a better value.

We offer more than 25 CF® Dyes in SE form. We also supply anhydrous DMSO, which can be used to prepare SE stock solutions that are stable at -20°C for up to one month. Our CF Dye and Biotin SE Protein Labeling Kits include everything you need for labeling and purification of 3 x 1 mg protein reactions. For fast and simple antibody labeling, also see our Mix-n-Stain™ Labeling Kits.

Our VivoBrite™ Rapid Antibody Labeling Kits for Small Animal Imaging include everything you need to prepare near-IR conjugates of our superior near-infrared CF® dyes for small animal imaging.

Cyanine NS succinimidyl esters are non-sulfonated cyanine dyes that can be used to label proteins, oligonucleotides and nucleic acids. Available in 3 colors, Cyanine 488NS, Cyanine 555NS, and Cyanine 647NS are non-sulfonated versions of Cy®2, Cy®3, and Cy®5, respectively. The dyes are designed to have matching charge and molecular weight for 2D DIGE platform. We also offer a wide selection of classic amine-reactive dye and biotinylation reagents.

CF® Dye Succinimidyl Esters, Protein Labeling Kits, & Related Products

ProductFeatures
CF® Dye Succinimidyl Esters• Amine-reactive chemistry widely used for protein and antibody labeling
• More than 25 bright & photostable CF® dye colors
• More stable SE for excellent labeling efficiency
CF® Dye & Biotin SE Protein Labeling Kits• Everything you need for labeling and purification of 3 x 1 mg protein reactions
• Wide selection of CF® dye colors plus biotin
VivoBrite™ Rapid Antibody Labeling Kits for Small Animal In Vivo Imaging• Everything you need for labeling and purification of 3 x 1 mg protein reactions for in vivo imaging
• Featuring our superior near-IR CF® dyes
Mix-n-Stain™ Labeling Kits• Simply and rapidly label small amounts of antibody with no purification required
• Label antibodies with CF® dyes, fluorescent proteins, tags, or enzymes
• Small ligand labeling kits available
Cyanine Dye SE• Structurally identical to Cy® dyes from GE Healthcare
• Cyanine 555 (Cy®3), Cyanine 647 (Cy®5), Cyanine 680 (Cy®5.5), & Cyanine 750 (Cy®7)
Cyanine NS SE• Non-sulfonated dyes with matching charge & MW for 2D DIGE
• Cyanine 488NS, Cyanine 555NS, and Cyanine 647NS
Classic Amine-Reactive Dyes & Biotin• Wide selection of classic amine-reactive dyes and biotinylation reagents
Anhydrous DMSO• Essential for preparation of SE stock solutions
Ultrafiltration Vials• For easy spin-column removal of free dye after labeling proteins
• 3K MWCO or 10K MWCO

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Thiol-reactive maleimide and MTS dyes

CF® Dye maleimides are thiol-reactive dyes. Maleimide reacts with thiol groups to form thioether-coupled products. The reaction can take place at pH 7 in the presence of amines. At neutral pH, the maleimide group does not react with histidine or arginine. Maleimide labeling can be a useful alternative to succinimidyl ester labeling in cases where modification of lysines alters antibody binding affinity or other biological activity of the target protein. We offer maleimide forms of more than 20 CF® dyes.

Methanethiosulfonate (MTS) is a fast-reacting and highly selective thiol-reactive functional group. We offer MTS with a selection of popular CF® dyes, biotin, classic dyes, and as thiol-modifying and cross-linking reagents.

We also offer many classic thiol-reactive dyes and biotin, as well as reducing agents commonly used in thiol conjugation protocols.

Thiol-Reactive CF® Dyes & Related Reagents

ProductFeatures
CF® Dye Maleimides• Commonly used thiol-reactive chemistry
• More than 20 bright & photostable CF® dye colors
CF® Dye MTS• Fast-reacting dyes with excellent thiol selectivity
• Available with a selection of popular CF® dyes
Other Thiol-Reactive Dyes & Compounds• Wide selection of classic dyes & biotin
MTS Thiol-Modification Reagents• Thiol-reactive methanethiosulfonate compounds and cross-linkers
• Useful for analysis of disulfide bonds in proteins
Reducing Agents• DTT & TCEP reducing agents frequently used for generating free thiols for labeling

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Dyes for labeling carbonyl groups and carbohydrates

Aminooxy reagents (also known as hydroxylamine or aminooxyacetamide) react with aldehydes or ketones to form a stable hydrazone compound under mild conditions without the use of a reducing agent. Aminooxy can be used to label abasic sites in damaged DNA or carbonyl groups resulting from protein oxidation. They also can be used to label carbohydrates or glycoproteins after oxidation of the carbohydrates to form carbonyl groups. The reaction is fast and can be further accelerated by adding aniline as a catalyst. Aminooxy reagents are superior labeling reagents to hydrazides, because they form more stable linkages.

Hydrazides also react with aldehydes or ketones, but form unstable hydrazone linkages. Hydrazides are non-toxic and highly water soluble, making them useful as fluid phase markers and fixable microinjectable cytoplasmic tracers.

We offer a wide selection of CF dye colors with aminooxy or hydrazide functional groups. We also offer CF®DI reactive dyes, which have matched molecular weight and charge for 2D DIGE platform. We also offer a wide selection of classic dyes and biotin in aminooxy and hydrazide forms.

Aminooxy & Hydrazide Reagents for Labeling Carbonyls and Carbohydrates

ProductFeatures
CF® Dye Aminooxy• Reacts with aldehydes & ketones to form stable linkage
• Wide selection of bright & photostable CF® dye colors
CF®DI Aminooxy• CF®DI aminooxy dyes have matching charge & MW for 2D DIGE
• Green fluorescent CF®DI 488, red fluorescent CF®DI 555, and far-red fluorescent CF®DI 647
Cyanine Dye Aminoxy• Cyanine 555 is structurally identical to Cy®3, while Cyanine 647 is structurally identical to Cy®5
CF® Dye Hydrazide• Reacts with aldehydes & ketones
• Useful polar tracers
• Wide selection of bright, photostable, and highly soluble CF® dye colors
CF®DI Hydrazide• CF®DI hydrazide dyes have matching molecular weight and charge
• Green fluorescent CF®DI 488, red fluorescent CF®DI 555, and far-red fluorescent CF®DI 647
Other Aminooxy & Hydrazide Reagents• Selection of classic dyes and biotin
Aniline, 10X in Acetate Buffer• Catalyst for aminooxy & hydrazide reactions

Cy3 and Cy5 are registered trademarks of GE Healthcare

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Dyes with a free amine group

CF® Dye Amines can be used to conjugate CF® dyes to carboxylic acids groups in biological molecules. After activation with water soluble carbodiimides, carboxylic acids react with amine-functionalized dyes to form a stable amide bond.

Dyes or biotin with amine groups like Lucifer Yellow Cadaverine or Neurobiotin™ are also used as fluid phase markers for neuronal tracing, as well as gap junction connectivity and dye permeability studies.

Dyes with an Amine Group