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Atto 425 NHS ester

BioReagent, suitable for fluorescence, ≥90% (HPLC)

Atto 425-N-hydroxysuccinimide ester
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
PubChem Substance ID:

Quality Level

product line



≥90% (HPLC)
≥90% (degree of coupling)




DMF: soluble
DMSO: soluble
H2O: soluble


in ethanol (with 0.1% trifluoroacetic acid)

UV absorption

λ: 422-428 nm Amax


suitable for fluorescence

storage temp.


SMILES string




InChI key


General description

Atto 425 is a member of the commercially available coumarin derivatives.


Atto 425 NHS ester is used in the development of bifunctional fluorescent, inorganic micro-partices (Zeolite L crystals) designed for targeting or imaging mutliple components . Reacts with amino groups or amine modified oliognucleotides to form a stable amine bond. Utilized as an essential component of molecular beacons, which were designed for use in real-time PCR assays to allow for rapid and accurate identification of gram-negative bacteria . When conjugated with benzylguanine, the fluorescence of Atto 425-NHS is quenched but becomes fluorescent upon labeling of the SNAP-tag fusion protein, making this conjugate an ideal candidate for experiments in living cells . Used as one of the donor probes in three-color FRET experiments designed to investigate the kinetics of RNA-protein complex formation .
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.

Other Notes

Study of stability during one- and two-photon excitation in fluorescence correlation spectroscopy, FCS; employed in triple-color coincidence analysis.

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.

Storage Class Code

11 - Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificate of Analysis

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Certificate of Origin

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P.S. Dittrich, P. Schwille
Applied Physics B: Lasers and Optics, 73, 829-829 (2001)
Handbook of Biophotonics: Vol. 2: Photonics for Health Care (2011)
Katrin G Heinze et al.
Biophysical journal, 86(1 Pt 1), 506-516 (2003-12-26)
Confocal fluorescence spectroscopy is a versatile method for studying dynamics and interactions of biomolecules in their native environment with minimal interference with the observed system. Analyzing coincident fluctuations induced by single molecule movement in spectrally distinct detection channels, dual-color fluorescence
Anna I Sulatskaya et al.
The journal of physical chemistry. B, 116(8), 2538-2544 (2012-01-25)
Benzothiazole dye thioflavin T (ThT) is a sensitive probe for amyloid fibril detection. The ThT probing is based on its unique ability to form highly fluorescent complexes with amyloid and amyloid-like fibrils. In this work we propose an approach of
Triple FRET: a tool for studying long-range molecular interactions.
Elke Haustein et al.
Chemphyschem : a European journal of chemical physics and physical chemistry, 4(7), 745-748 (2003-08-07)

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