Phenoxazone 660 | CAS 16650-80-9

Phenoxazone 660 is a phenoxazine-based fluorescent dye designed for red-emitting fluorescence workflows, typically used as a molecular labeling and imaging reagent in chemical biology and analytical microscopy. Its extended conjugation supports strong visible-region emission, and its dye-like small-molecule format makes it convenient for incorporation into labeled constructs and fluorescence readouts where robust red fluorescence is required. Researchers often pair Phenoxazone 660 with standard fluorescence instrumentation to visualize distribution, track labeling, and support fluorescence-based assay development.

1. Fluorescence Microscopy Labeling

Phenoxazone 660 is used as a red fluorescent labeling dye for microscopy studies where researchers need to visualize tagged biomolecules, polymers, or prepared staining reagents with emission in the far-red/red spectral region. In practice, it supports fluorescence imaging workflows for fixed or prepared samples, including multicolor experiments where its emission helps separate the signal from common green/yellow fluorophores. Imaging teams often incorporate the dye into labeling reagents for tracking localization patterns, validating conjugation outcomes, or monitoring distribution in microscopy sample preparations.

2. Fluorescent Bioassay Tracing

Phenoxazone 660 is applied in fluorescence-based bioassays and analytical tracing experiments that rely on red fluorescence as the measurable reporter. Lab groups use it to construct fluorescent readouts for monitoring binding or association events in labeled assay formats, as well as for tracking labeled components in reaction mixtures and assay development pipelines. Because the dye is a small-molecule fluorophore, it is frequently selected when a compact fluorescent reporter is needed to tag assay components, enabling straightforward incorporation into experimental protocols that quantify fluorescence intensity using plate readers or benchtop fluorometers.

3. Polymer And Biomaterial Staining

Phenoxazone 660 is commonly used to stain or label polymeric materials and biomaterial surfaces for fluorescence visualization and materials characterization. Researchers apply the dye to prepared polymer films, coatings, hydrogels, or functionalized surfaces to assess distribution, uniformity, and retention of fluorescent labeling after processing steps. Materials scientists also use Phenoxazone 660 in microscopy-based studies to compare labeled formulations and to visualize how fluorescently tagged components localize within or on structured materials, supporting iterative development of fluorescently traceable biomaterials.

4. Fluorescent Probe Construction

Phenoxazone 660 is leveraged as a fluorophore building block for fluorescence probe development when a red-emitting reporter is desired. Chemical biology teams incorporate the dye into custom fluorescent conjugates to generate labeled probes for detection workflows that read out fluorescence from the reporter moiety. In these projects, Phenoxazone 660 is selected for its compatibility with fluorescence instrumentation used in research settings and for its usefulness as a spectrally distinct reporter in probe constructs designed for downstream imaging, screening, or analytical readouts.