ATTO 488 NHS ester | CAS 863772-22-9

ATTO 488 NHS ester is a reactive fluorescein-like green fluorescent dye designed for efficient covalent labeling of primary amines via NHS ester chemistry. The bright ATTO 488 emission supports fluorescence microscopy and quantitative fluorescence readouts, while the activated ester format enables straightforward conjugate preparation for proteins, peptides, and other amine-containing biomolecules used in imaging and assay development.

1. Protein And Antibody Labeling

ATTO 488 NHS ester is widely used to generate fluorescent protein conjugates for immunofluorescence workflows and antibody-based labeling experiments. Researchers typically employ it to tag purified antibodies, antibody fragments, enzymes, or binding proteins for visualization of biomolecular interactions in fixed-cell imaging, as well as for fluorescence-based binding assays where a stable covalent dye-to-protein linkage is required. Because the reagent targets primary amines, it is also commonly used to label carrier proteins and affinity reagents that contain lysine residues, supporting downstream use in microscopy, plate-based fluorescence assays, and characterization of labeled conjugates.

2. Fluorescence Microscopy Staining

ATTO 488 NHS ester supports fluorescence microscopy staining of amine-bearing targets in cellular and biomaterials contexts, including fluorescent labeling of extracellular matrix components, cell-surface proteins, and fixed-sample labeling strategies. Imaging teams use the dye-conjugated biomolecules as probes for localization studies, enabling green-channel visualization on standard fluorescence microscopes equipped for ATTO 488-compatible excitation and emission. The covalent NHS ester labeling format helps reduce dye loss associated with noncovalent staining, which is particularly useful when washing steps and multi-step staining protocols are part of the microscopy workflow.

3. Flow Cytometry Conjugate Preparation

ATTO 488 NHS ester is frequently used in flow cytometry reagent development to prepare fluorescent antibody conjugates and other amine-reactive labeling reagents for cell-surface or intracellular marker studies in fixed or permeabilized sample formats. Flow cytometry users rely on the dye's strong green fluorescence to quantify labeled populations and to build multicolor panels where ATTO 488 serves as a defined spectral channel. The NHS ester reactivity toward lysine-containing biomolecules enables consistent conjugate construction for assay standardization and for generating detection reagents used in gating and comparative studies across experimental conditions.

4. Fluorescent Bioassay Reagent Development

ATTO 488 NHS ester is used to construct fluorescent assay reagents by labeling amine-containing proteins and peptides that act as reporters, binding partners, or assay components. In fluorescence-based bioassays, the dye's emission supports monitoring of binding, immobilization, or signal generation in plate readers and imaging-compatible formats, where covalent dye attachment helps maintain reagent stability during incubation and washing. This reagent format is also commonly leveraged in assay optimization workflows to create labeled standards and calibration materials for quantitative fluorescence readouts.