Atto 425 NHS ester

BioReagent, suitable for fluorescence

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

Quality Level

product line



DMF: soluble
DMSO: soluble
H2O: soluble


λex 437 nm; λem 483 nm in 0.1 M phosphate pH 7.0


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.

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

Handbook of Biophotonics: Vol. 2: Photonics for Health Care (2011)
P.S. Dittrich, P. Schwille
Applied Physics B: Lasers and Optics, 73, 829-829 (2001)
Richard S Agnes et al.
Journal of the American Chemical Society, 132(17), 6075-6080 (2010-04-13)
A fluorescent sensor of protein kinase activity has been developed and used to characterize the compartmentalized location of cAMP-dependent protein kinase activity in mitochondria. The sensor functions via a phosphorylation-induced release of a quencher from a peptide-based substrate, producing a...
Nermin Seda Kehr et al.
Nanoscale, 2(4), 601-605 (2010-07-21)
Microcontact printing (mCP) is used to immobilize dyes and peptides asymmetrically, by a "peptide coupling" reaction, on monolayers of zeolite L crystals in the contact area between the stamp and the surface of the monolayer. Chemically patterned surfaces of monolayers...
Frequency domain fluorescence microspectrometry: Application to cellular uptake and drug distribution.
Praus, P., et al.
Spectroscopy: An International Journal, 24, 303-307 (2010)

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