Cyanine5.5 dye | CAS 1449661-34-0

Cyanine5.5 dye is a near-infrared cyanine fluorophore designed for bright fluorescence labeling in imaging and fluorescence-based assays. Its extended conjugation provides excitation and emission well-suited for optical detection with common fluorescence instrumentation, while its dye core supports straightforward conjugate preparation when paired with appropriate labeling chemistries. Researchers use Cyanine5.5 dye to generate fluorescent tracers and conjugates for sensitive visualization workflows where reduced background from longer-wavelength imaging is advantageous.

1. Fluorescence Microscopy Imaging

Cyanine5.5 dye is frequently used as a labeling fluorophore for fluorescence microscopy studies that track biomolecule localization, uptake, and trafficking in fixed samples and labeled specimens. In practice, it is incorporated into antibody, peptide, or polymer conjugates so that targets can be visualized with far-red/near-infrared channel imaging, supporting multicolor experiments where spectral separation from visible dyes is required. Imaging teams also rely on Cyanine5.5 dye-containing conjugates for time-course studies in which consistent fluorescence readout is needed for comparative visualization across experimental conditions.

2. Flow Cytometry Fluorescent Labeling

Cyanine5.5 dye is commonly selected for flow cytometry panels to label proteins, antibodies, or other targeting ligands for cell-associated readouts. The dye's far-red emission enables gating strategies that reduce spectral overlap with many green and red fluorophores, which is particularly useful when building multiplexed cytometry assays. Cytometry workflows often use Cyanine5.5 dye conjugates as stable fluorescent tags for quantifying relative labeling intensity on cell surfaces or within labeled populations, supporting phenotyping and biomolecule binding studies.

3. Fluorescence Bioassay Development

Cyanine5.5 dye is widely used in fluorescence assay development where a far-red reporter improves optical discrimination in plate-based and cuvette-based formats. Assay developers incorporate the dye into detection reagents such as fluorescently labeled affinity binders, secondary reagents, or reporter conjugates to generate measurable fluorescence signals that correlate with binding events, reagent interactions, or assay-specific readouts. In biosensor and binding-assay development, Cyanine5.5 dye-labeled components are used to construct fluorescence-based detection schemes compatible with standard fluorescence readers, enabling robust signal generation for assay optimization and method development.

4. Fluorescent Tracer and Conjugate Preparation

Cyanine5.5 dye is routinely used as a modular fluorophore for preparing fluorescent tracers and conjugates for molecular imaging reagent research. Conjugate chemists attach the dye to biomolecules, nanoparticles, or polymer scaffolds using established labeling strategies compatible with cyanine fluorophores, producing reagents that can be used for localization, distribution, and binding studies. This application is especially common in translational research workflows where investigators need a far-red fluorescent tag for visualizing labeled constructs in complex sample matrices, including multicomponent biological preparations and engineered materials.