ATTO 425 acid is manufactured by AAT Bioquest for research and development use. ATTO 425 is a coumarin-based fluorescent dye characterized by its high fluorescence quantum yield, large Stokes shift, excellent photostability, and low molecular weight. It exhibits moderate hydrophilicity and is optimally excited in the 405–455 nm wavelength range. These properties make ATTO 425 particularly suitable for applications in single-molecule detection and high-resolution microscopy techniques, including PALM, dSTORM, and STED microscopy. Additionally, ATTO 425 is well-suited for use in flow cytometry (FACS), fluorescence in situ hybridization (FISH), and various other biological assays.

ATTO 425 acid is a non-reactive compound that can be employed as a reference standard in studies utilizing ATTO 425 conjugates. It is also suitable for use as a control in confocal microscopy, immunocytochemistry (ICC), high-content screening (HCS), flow cytometry, and live cell imaging applications. Furthermore, it can be utilized in the synthesis of activated esters and STP and can be coupled to hydrazines, hydroxylamines, or amines in aqueous solutions using water-soluble carbodiimides (e.g., EDAC). This allows for the conjugation of the dye to amino-containing molecules, such as proteins, antibodies, amine-modified oligonucleotides, and peptides.