ATTO 620 NHS ester

ATTO 620 NHS ester is a reactive, NHS-ester functionalized ATTO 620 fluorophore designed for efficient covalent fluorescent labeling of primary amine-containing biomolecules and materials. Its red-orange emission makes it a common choice for multi-color fluorescence workflows where separation from green and yellow channels is required. The activated ester enables straightforward preparation of fluorescent conjugates for microscopy, imaging, and fluorescence-based assay development.

1. Protein And Antibody Labeling

ATTO 620 NHS ester is widely used to generate fluorescently labeled proteins, antibodies, and affinity reagents by targeting lysine residues and N-termini. Researchers employ ATTO 620 conjugates for fluorescence microscopy of labeled targets, for binding studies where a stable dye tag is needed, and for preparing fluorescent secondary reagents in immunostaining workflows. The NHS-ester reactivity supports labeling of purified biomolecules and conjugate standards used in assay development and imaging method validation.

2. Fluorescence Microscopy Tracing

ATTO 620 NHS ester supports cellular and biomolecular tracing experiments where red-channel imaging improves contrast and reduces spectral overlap with common green fluorophores. Laboratories use ATTO 620-labeled proteins or polymers to visualize adsorption, uptake, trafficking, or spatial distribution in fixed or prepared samples, including co-localization studies with spectrally distinct dyes. The dye's bright red emission is particularly helpful for imaging workflows on widefield and confocal microscopes, as well as for building multi-color panels that require robust separation across channels.

3. Flow Cytometry Labeling

ATTO 620 NHS ester is used to prepare flow cytometry-compatible fluorescent conjugates for labeling cell-surface proteins, receptor-binding reagents, and other amine-containing targets in suspension assays. Researchers generate ATTO 620-labeled antibodies or protein probes to quantify binding by fluorescence readout, enabling gating and population analysis in multiplex staining schemes where a red-emitting dye is advantageous. The NHS-ester chemistry is commonly selected when a stable covalent label is preferred over noncovalent dye association.

4. Fluorescence Bioassay Reagent Development

ATTO 620 NHS ester is frequently incorporated into fluorescent reagent development for plate-based assays and molecular interaction studies that rely on covalent dye tagging. Assay developers use ATTO 620-labeled proteins, peptides, or affinity reagents to construct fluorescence readouts for binding assays, labeling controls, and calibration materials. The activated ester functionality streamlines preparation of consistent fluorescent conjugates for method development, reagent screening, and fluorescence-based characterization of biomolecular systems.