Oregon Green 488 carboxylic acid | CAS 195136-52-8

Oregon Green 488 carboxylic acid is a fluorescein-based green fluorescent dye designed for covalent attachment through its carboxylic acid functionality. In fluorescence labeling workflows, it is commonly used to prepare dye conjugates for microscopy and fluorescence-based assays where strong visible excitation and convenient conjugation chemistry are required. Its anionic, dye-like properties make it a widely adopted reporter for tracking biomolecules and for constructing fluorescent labeling reagents compatible with standard fluorescence instrumentation.

1. Protein And Antibody Labeling

Oregon Green 488 carboxylic acid is frequently used by protein chemistry and immunoassay groups to generate fluorescently labeled antibodies, affinity reagents, and protein conjugates for binding and localization studies. After activation and coupling to primary amine-containing biomolecules, the resulting Oregon Green 488 conjugates are used in fluorescence microscopy and plate-based fluorescence assays to quantify binding events, follow reagent distribution, and compare labeled targets across experimental conditions. Researchers also rely on this dye class for building consistent labeling reagents where the fluorescein emission in the green channel aligns well with common filter sets and detector configurations.

2. Fluorescence Microscopy Tracing

Oregon Green 488 carboxylic acid is widely applied in cellular and biomaterials imaging workflows to visualize labeled biomolecules and to trace transport or localization patterns in microscopy experiments. Fluorescent conjugates derived from this dye are used to tag proteins, peptides, and other macromolecules that are then imaged under standard fluorescence microscopes using green excitation/emission detection. In practice, the dye's bright, water-compatible fluorescence supports routine imaging of labeled samples, including multicolor experiments where green-channel reporters are combined with spectrally distinct dyes for cellular imaging and colocalization analysis.

3. Flow Cytometry Labeling

Oregon Green 488 carboxylic acid is used in flow cytometry reagent development when green fluorescent labeling of biomolecules is needed for cell-associated readouts. Dye-conjugated antibodies and labeling reagents prepared from this carboxylic acid are commonly used to stain cell-surface or intracellular targets in fixed or permeabilized workflows, enabling quantitative fluorescence measurements by flow cytometry. This application is particularly common in assay development and screening environments where standardized fluorescent labeling reagents are required to compare signal across samples using green fluorescence detection channels.

4. Fluorescent Bioassay Development

Oregon Green 488 carboxylic acid is also used to construct fluorescence-based assay reagents, including labeled substrates, detection conjugates, and tracer molecules for plate reader measurements. In biochemical and chemical biology workflows, Oregon Green 488 conjugates serve as fluorescent reporters for binding assays, reagent tracking, and endpoint fluorescence readouts where a stable green fluorophore is advantageous. Assay developers frequently choose this dye class to integrate fluorescent labeling into assay formats that rely on excitation/emission detection in the visible range and straightforward handling of dye-labeled conjugates.