3-(5-carboxypentyl)-1,1,2-trimethyl-1H-benzo[e]indol-3-ium bromide

This compound serves as a key intermediate in the synthesis of cyanine-based fluorescent dyes, offering good water solubility and ionic characteristics. It is widely used in the development of biomolecular labels, optical probes, and fluorescent dyes. Typical applications include molecular imaging, labeling of DNA/RNA probes, biosensors, flow cytometry, fluorescence microscopy, and near-infrared imaging in life sciences and medical diagnostics.