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A heptamethine fluorophore, <b>ERB-60</b>, has been synthesized efficiently in four steps in a good yield. The structure of this fluorophore consists of an electron-donating group (methoxy), a hydrophobic moiety (phenylpropyl) with a rotatable bond, a quaternary ammonium fragment, and indolium rings at the terminal ends connected via polymethine chain. All these inherent chemical features fine-tuned the optical properties of the fluorophore. This compound was characterized by both ¹H NMR, ¹³C NMR and mass spectra. The optical properties, including molar absorptivity, fluorescence, Stokes’s shift, and quantum yield, were measured in different solvents such as DMSO, DMF, MeCN, <i>i</i>-PrOH, MeOH, and H₂O. The wavelengths of maximum absorbance of <b>ERB-60</b> were found to be in the range of 745–770 nm based on the solvents used. In decreasing order, the maximum wavelength of absorbance of <b>ERB-60</b> in the tested solvents was DMSO > DMF > <i>i</i>-PrOH > MeOH > MeCN > H₂O while the decreasing order of the extinction coefficient was found to be MeCN > MeOH > DMSO > <i>i-</i>PrOH > H₂O > DMF. <b>ERB-60</b> was found to be more photostable than <b>IR-786 iodide</b>, a commercially available dye, and brighter than the FDA-approved dye, indocyanine green (ICG).