Atto 655

BioReagent, suitable for fluorescence, ≥85% (HPLC)

MDL number:
PubChem Substance ID:

Quality Level

product line



≥85% (HPLC)


λex 655 nm; λem 680 nm in 0.1 M phosphate pH 7.0


suitable for fluorescence

storage temp.




InChI key


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Atto labels are designed for highest sensitivity applications. A unique combination of advantages makes them highly favorable tools for all kinds of labeling applications. Some of their properties make them specifically interesting for single molecule detection. Atto labels are based on rigid structures and do not show any cis-trans-isomerization, which lowers the brightness of signals and leads to environment dependency, e.g., spectral shifts by conjugation.
Atto 655 shows a molar extinction of 110,000 and QY of 30% in water (50% in ethanol). Decay time is 1.9 ns.

Other Notes

New red absorbing fluorescent dye with best signal-to-noise ratio and long fluorescence life-time. Useful as a biophysical probe for binding interactions.

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

Volker Buschmann et al.
Bioconjugate chemistry, 14(1), 195-204 (2003-01-16)
The spectroscopic characteristics (absorption, emission, and fluorescence lifetime) of 13 commercially available red-absorbing fluorescent dyes were studied under a variety of conditions. The dyes included in this study are Alexa647, ATTO655, ATTO680, Bodipy630/650, Cy5, Cy5.5, DiD, DY-630, DY-635, DY-640, DY-650...
Bengang Xing et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 17(50), 14170-14177 (2011-11-16)
The molecular interactions of the glycopeptide antibiotic vancomycin (Van) with bacterial cell wall analogues N,N'-diacetyl-L-Lys-D-Ala-D-Ala (Ac(2) KdAdA) and N,N'-diacetyl-L-Lys-D-Ala-D-Lac (Ac(2) KdAdL) were investigated in neat water, phosphate buffer and HEPES buffer by using fluorescence correlation spectroscopy (FCS) and molecular dynamics...
Eilon Sherman et al.
Chemphyschem : a European journal of chemical physics and physical chemistry, 12(3), 696-703 (2011-01-29)
Intramolecular dynamics in the denatured state of a protein are of importance for protein folding. Native-like contact formation within the ensemble of denatured conformations of a protein may guide its transformation towards the native conformation. The efficiency of folding is...
Achim Friedrich et al.
FEBS letters, 581(8), 1644-1648 (2007-04-03)
This article presents a new, highly sensitive method for the identification of single nucleotide polymorphisms (SNPs) in homogeneous solutions using fluorescently labeled hairpin-structured oligonucleotides (smart probes) and fluorescence single-molecule spectroscopy. While the hairpin probe is closed, fluorescence intensity is quenched...
Julie M G Rogers et al.
Langmuir : the ACS journal of surfaces and colloids, 27(7), 3815-3821 (2011-03-16)
The structure and function of the influenza A M2 proton channel have been the subject of intensive investigations in recent years because of their critical role in the life cycle of the influenza virus. Using a truncated version of the...

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