Atto 520

BioReagent, suitable for fluorescence, ≥90.0% (HPCE/HPLC)

Empirical Formula (Hill Notation):
Molecular Weight:
MDL number:
PubChem Substance ID:
Pricing and availability is not currently available.

Quality Level

product line



≥90.0% (HPCE/HPLC)


λex 520 nm; λem 540 nm in 0.1 M phosphate pH 7.0


suitable for fluorescence

storage temp.


SMILES string




InChI key


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Atto fluorescent labels are designed for high sensitivity applications, including single-molecule detection. Atto labels have rigid structures that do not show any cis-trans isomerization. Thus these labels display exceptional intensity with minimal spectral shift on conjugation.
Atto 520 shows a molar extinction of 110,000 and QY of 90% in water (95% in ethanol). Decay time is 3.6 ns.

Other Notes

Employed in confocal fluorescence microscopy to confirm formation of polymer nanoshells; using combined imaging and scanning fluorescence correlation spectroscopy to characterize microsecond emission fluctuation.

Legal Information

This product is for Research use only. In case of intended commercialization, please contact the IP-holder (ATTO-TEC GmbH, Germany) for licensing.

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

Ying Xiao et al.
Analytical chemistry, 77(1), 36-46 (2004-12-30)
In this report, a combined imaging and fluorescence correlation spectroscopy (FCS) method is described and its ability to characterize microsecond fluctuations in the fluorescence emission of a sample is demonstrated. A sample scanning laser confocal microscope is operated in the...
Alexander B Artyukhin et al.
Langmuir : the ACS journal of surfaces and colloids, 20(4), 1442-1448 (2005-04-05)
Carbon nanotubes have been featured prominently in the nanotechnology research for some time, yet robust strategies for noncovalent chemical modification of the nanotube surface are still missing. Such strategies are essential for the creation of functional device architectures. Here, we...
Siddharth Nanguneri et al.
PloS one, 7(5), e38098-e38098 (2012-06-05)
Three-dimensional fluorescence imaging of thick tissue samples with near-molecular resolution remains a fundamental challenge in the life sciences. To tackle this, we developed tomoSTORM, an approach combining single-molecule localization-based super-resolution microscopy with array tomography of structurally intact brain tissue. Consecutive...
Vladimir Mekler et al.
The Journal of biological chemistry, 286(1), 270-279 (2010-10-19)
Promoter recognition by RNA polymerase is a key point in gene expression and a target of regulation. Bacterial RNA polymerase binds promoters in the form of the holoenzyme, with the σ specificity subunit being primarily responsible for promoter recognition. Free...
Hee-Jin Jeong et al.
Biosensors & bioelectronics, 40(1), 17-23 (2012-07-17)
Protein phosphorylation is a key event in intracellular signal transduction, and fluorescent biosensor for the specific phosphorylation event in a target protein is considered highly useful as a tool of cellular biology and drug screening. Vimentin, the most abundant intermediate...

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