Conjugates prepared with the amine-reactive Alexa Fluor® 790 carboxylic acid, succinimidyl ester have spectra similar to that of indocyanine green (ICG) and the IRDye® 800 dye, with 784/814 nm excitation/emission maxima. As the longest-wavelength Alexa Fluor® dye, the emission is well separated from commonly used far-red fluorophores such as Alexa Fluor® 647 dye or allophycocyanin (APC), facilitating multicolor analysis. This fluorophore is also expected to be useful for small animal in-vivo imaging (SAIVI) applications or for two-color western applications with the LI-COR® Odyssey® infrared imaging system.