ATTO 532 NHS ester | CAS 924660-19-5

ATTO 532 NHS ester is a reactive fluorescent dye designed for efficient amide coupling to primary amine groups on proteins, peptides, and other biomolecules. As an NHS-ester, it supports straightforward fluorescent labeling workflows, enabling bright red-orange fluorescence for microscopy and fluorescence-based assays. Its ATTO 532 chromophore is widely used in labeling applications where robust signal generation and convenient conjugate preparation are required.

1. Protein Fluorescent Labeling

ATTO 532 NHS ester is frequently used by bioconjugation and proteomics researchers to generate fluorescently labeled proteins for imaging, binding studies, and fluorescence readouts in assay development. The NHS-ester reacts with lysine side-chain amines and N-terminal amines, making it a practical choice for labeling antibodies, enzymes, transport proteins, and affinity reagents used in downstream fluorescence microscopy or plate-based measurements. Labeled proteins prepared with ATTO 532 NHS ester are commonly incorporated into workflows that require stable covalent attachment rather than passive adsorption, supporting consistent staining and quantification across experimental replicates.

2. Fluorescence Microscopy Staining

ATTO 532 NHS ester is used to prepare fluorescent conjugates for cellular and molecular microscopy experiments where amine-containing targets need to be visualized. Researchers label proteins and protein-rich materials such as extracellular matrix components, antibody probes, and surface-associated biomolecules to map localization, track binding, or visualize distribution patterns on cells and biomaterial surfaces. The dye's emission in the visible range supports routine fluorescence microscopy configurations, including standard filter sets used for green-to-orange/red channel imaging, enabling multiplexing strategies when paired with spectrally separated fluorophores.

3. Flow Cytometry Conjugate Preparation

ATTO 532 NHS ester is widely applied in flow cytometry reagent development to fluorescently label antibodies and other amine-bearing targeting proteins used for cell-surface or intracellular staining workflows. By covalently attaching ATTO 532 to lysines, researchers create conjugates that can be used in staining panels for fluorescence readout on common flow cytometers with appropriate excitation/emission detection settings. This labeling approach is particularly useful when reproducible labeling intensity and covalent stability are important for comparing populations across time-course experiments, optimization studies, and method development for fluorescence-based phenotyping assays.

4. Fluorescent Bioassay Reagent Development

ATTO 532 NHS ester supports the preparation of fluorescent assay reagents by labeling enzymes, binding proteins, and assay components that report biochemical interactions through fluorescence intensity or localization. In fluorescence-based bioassays, covalently labeled proteins prepared with ATTO 532 NHS ester can be used as detection reagents, standards, or signal-generating components in plate formats and imaging-based readouts. The dye's compatibility with common fluorescence instrumentation makes it a practical choice for researchers building custom assay reagents, including conjugate-based binding assays and fluorescence tracking experiments in chemical biology and molecular imaging workflows.