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AAT Bioquest

XFD660 alkyne

Product key features

  • Ex/Em: 663/691 nm
  • Extinction coefficient: 132,000 cm-1M-1
  • Superior Fluorescence Performance: High quantum yield, exceptional photostability, and pH-independent fluorescence across pH 4–11.
  • Reactive Group: Alkyne
  • Efficient Conjugation: Click chemistry labeling of azides on peptides, antibodies, and other biomolecules
  • High Water-Solubility: Prevents aggregation and enhances signal clarity for advanced imaging and live-cell applications

Product description

XFD660, manufactured by AAT Bioquest, is a far-red fluorescent dye structurally equivalent to Alexa Fluor™ 660 (ThermoFisher). The dye demonstrates high fluorescence quantum yield, photostability, and aqueous solubility, with pH-independent fluorescence across a broad range (pH 4–11), providing consistent performance across diverse experimental conditions.

XFD660 is optimized for red laser excitation and is compatible with flow cytometers equipped with spectral detection systems. It provides robust and uniform labeling with high signal intensity and reproducibility, making it ideal for fluorescence imaging, flow cytometry, and other analytical techniques. XFD660 demonstrates versatility in labeling a wide range of targets, including cell surface, intracellular, and intranuclear antigens. Its spectral properties position it between XFD647 and XFD700, making it a valuable intermediate fluorophore for constructing complex multicolor panels and enabling precise experimental designs in advanced research workflows.

The alkyne derivative of XFD660 is widely used for labeling azides on peptides, antibodies, and other biomolecules via click chemistry. It participates in copper-catalyzed azide-alkyne cycloaddition (CuAAC) with azide-containing molecules.

Spectrum

Product family

NameExcitation (nm)Emission (nm)Extinction coefficient (cm -1 M -1)Quantum yieldCorrection Factor (260 nm)Correction Factor (280 nm)
XFD350 alkyne34344119000-0.250.19
XFD405 alkyne40142135,000-0.230.70
XFD430 alkyne43254015,000--0.28
XFD488 alkyne *Same Structure to Alexa Fluor™ 488 alkyne*499520710000.9210.300.11
XFD514 alkyne51854380000-0.310.18
XFD532 alkyne534553810000.6110.240.09
XFD546 alkyne5615721120000.7910.210.12
XFD555 alkyne5535681500000.110.080.08
XFD568 alkyne579603913000.6910.450.46
XFD594 alkyne590618900000.6610.430.56
XFD610 alkyne611629144,000-0.430.44
XFD633 alkyne632650159,000--0.55
XFD635 alkyne633647140,000---
XFD647 Alkyne6506712700000.331-0.03
XFD660 TCO663691132000-0.000.10
XFD660 Tetrazine663691132000-0.000.10
XFD680 alkyne6817041840000.3610.000.05
XFD700 alkyne6967191920000.2510.000.07
XFD750 alkyne7527762400000.1210.000.04
XFD790 alkyne782805260,000-0.090.08
Show More (11)
Page updated on June 22, 2025

Ordering information

Price
Unit size
Catalog Number70095
Quantity
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Additional ordering information

Telephone1-800-990-8053
Fax1-800-609-2943
Emailsales@aatbio.com
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Purchase orderSend to sales@aatbio.com
ShippingStandard overnight for United States, inquire for international
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Physical properties

Solvent

DMSO

Spectral properties

Correction Factor (260 nm)

0.00

Correction Factor (280 nm)

0.10

Extinction coefficient (cm -1 M -1)

132000

Excitation (nm)

663

Emission (nm)

691

Storage, safety and handling

H-phraseH303, H313, H333
Hazard symbolXN
Intended useResearch Use Only (RUO)
R-phraseR20, R21, R22

Storage

Freeze (< -15 °C); Minimize light exposure
UNSPSC12171501
Schematic illustrating the azide–alkyne cycloaddition (“click chemistry”) between an alkyne‐functionalized dye and an azide‐presenting biomolecule. In the presence of a copper catalyst (CuAAC) or under strain‐promoted conditions (SPAAC), the azide and alkyne react to form a stable 1,2,3‐triazole linkage. This highly selective and robust reaction proceeds under mild conditions, tolerates a wide range of functional groups, and is frequently used to label proteins, nucleic acids, and other biomolecules for imaging, proteomics, and high‐throughput assays.
Schematic illustrating the azide–alkyne cycloaddition (“click chemistry”) between an alkyne‐functionalized dye and an azide‐presenting biomolecule. In the presence of a copper catalyst (CuAAC) or under strain‐promoted conditions (SPAAC), the azide and alkyne react to form a stable 1,2,3‐triazole linkage. This highly selective and robust reaction proceeds under mild conditions, tolerates a wide range of functional groups, and is frequently used to label proteins, nucleic acids, and other biomolecules for imaging, proteomics, and high‐throughput assays.
Schematic illustrating the azide–alkyne cycloaddition (“click chemistry”) between an alkyne‐functionalized dye and an azide‐presenting biomolecule. In the presence of a copper catalyst (CuAAC) or under strain‐promoted conditions (SPAAC), the azide and alkyne react to form a stable 1,2,3‐triazole linkage. This highly selective and robust reaction proceeds under mild conditions, tolerates a wide range of functional groups, and is frequently used to label proteins, nucleic acids, and other biomolecules for imaging, proteomics, and high‐throughput assays.