2-[(1E,3Z,5E,7E)-4-Carboxy-7-(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidene)-1,3,5-heptatrien-1-yl]-1,3,3-trimethyl-3H-indolium Iodide | CAS 2311980-68-2

This indolium-based fluorescent dye features a conjugated polymethine framework and a carboxylic acid functional group, enabling covalent attachment or incorporation into labeling workflows while providing strong visible fluorescence for imaging and assay development. The indolium chromophore is commonly leveraged as a bright, photostable reporter in fluorescence-based molecular staining and probe construction, including formats where controlled conjugation is required for downstream bioconjugates.

1. Bioconjugate Fluorescent Labeling

2-[(1E,3Z,5E,7E)-4-Carboxy-7-(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidene)-1,3,5-heptatrien-1-yl]-1,3,3-trimethyl-3H-indolium Iodide is used as a fluorescent labeling reagent for preparing dye-conjugated biomolecules in chemical biology workflows. Researchers typically couple the dye's carboxyl group to amine-bearing targets (for example, proteins, peptides, or engineered biomolecular scaffolds) to generate stable fluorescent conjugates for tracking, localization studies, and reagent development. In practice, the indolium chromophore supports bright signal generation in fluorescence microscopy and plate-based fluorescence assays, making it useful when fluorescent conjugates must be prepared in defined stoichiometry for comparative imaging experiments.

2. Fluorescence Microscopy Staining

2-[(1E,3Z,5E,7E)-4-Carboxy-7-(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidene)-1,3,5-heptatrien-1-yl]-1,3,3-trimethyl-3H-indolium Iodide is applied in fluorescence microscopy to visualize labeled biomolecular assemblies and dye-tagged materials. In microscopy workflows, the dye is commonly incorporated into conjugates that bind or associate with cellular components through the attached targeting handle introduced during conjugation, enabling visualization of structures in fixed or prepared samples where washing and imaging readouts are central. The carboxyl functionality also supports straightforward integration into multi-component staining schemes, including sequential labeling strategies where the fluorescent signal must remain robust during imaging and post-stain handling.

3. Fluorescence-Based Bioassay Development

2-[(1E,3Z,5E,7E)-4-Carboxy-7-(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidene)-1,3,5-heptatrien-1-yl]-1,3,3-trimethyl-3H-indolium Iodide is frequently used to construct fluorescent readouts for assay development in research laboratories. The dye's strong fluorescence is leveraged to generate labeled reagents for monitoring binding events, tracking reagent incorporation, or reporting on assay progress in microplate formats. Because the dye includes a carboxylic acid group, it can be engineered into conjugate-based assay components, such as fluorescently tagged affinity reagents or labeled probes used to quantify interactions by endpoint fluorescence measurements. This makes it a practical choice for teams developing fluorescence assays that require a bright, conjugation-ready reporter.

4. Polymer And Biomaterial Surface Functionalization

2-[(1E,3Z,5E,7E)-4-Carboxy-7-(1,3,3-trimethyl-1,3-dihydro-2H-indol-2-ylidene)-1,3,5-heptatrien-1-yl]-1,3,3-trimethyl-3H-indolium Iodide supports fluorescence-guided materials research through incorporation into polymer and biomaterial surface functionalization strategies. Materials scientists use the dye as a fluorescent tag to verify surface modification, quantify coating uniformity, or visualize labeled biomolecule adsorption on engineered substrates. The presence of a carboxylic acid handle enables covalent attachment approaches to amine-functionalized surfaces or biomaterial coatings, allowing the dye to be immobilized for stable imaging and analytical readouts during material characterization and process development.