Atto 520 maleimide

for fluorescence, ≥90% (coupling rate)

Empirical Formula (Hill Notation):
Molecular Weight:
PubChem Substance ID:

Quality Level


for fluorescence


≥90% (coupling rate)


DMF: soluble
DMSO: soluble
acetonitrile: soluble


passes test for fluorescence

storage temp.


SMILES string




InChI key



Atto 520 maleimide utilized for labeling sulfhydryl (thiol) groups of proteins, especially cysteine residues, to fluorescently study changes in conformation, binding, and kinetics .
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.

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.

Certificate of Analysis

Certificate of Origin

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...
Christopher A Teske et al.
The journal of physical chemistry. B, 109(28), 13811-13817 (2006-07-21)
Confocal laser scanning microscopy (CLSM) is being increasingly used for observing protein uptake in porous chromatography resins. Recent CLSM studies have revealed the possible existence of a nondiffusive protein transport mechanism. Observing protein uptake with CLSM requires labeling the protein...
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...
Manoj Kumbhakar et al.
Chemphyschem : a European journal of chemical physics and physical chemistry, 10(4), 629-633 (2009-01-30)
Complex dynamics of combined long-range fluorescence resonance energy transfer (FRET) and short-range electron transfer (ET) processes in a single double-stranded DNA (dsDNA) molecule (see figure) reveals that FRET remains almost unaltered in the presence of ET. Present systems also demonstrate...
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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