iFluor® 647–dextran conjugate (average molecular weight ~20,000 Da) is a hydrophilic, far-red fluorescent tracer composed of a 20 kDa dextran polymer covalently labeled with iFluor® 647. This dye exhibits excitation and emission maxima at approximately 656 nm and 670 nm, respectively, making it compatible with standard 633 nm and 640 nm laser excitation used in flow cytometry and fluorescence microscopy platforms. The intermediate molecular weight of the dextran backbone offers favorable diffusion properties while maintaining moderate exclusion from intracellular compartments, making this conjugate particularly suitable for applications such as endocytosis tracking, vascular permeability assays, and macromolecular transport studies.

iFluor® 647 is spectrally comparable to Alexa Fluor® 647 and Cy5, providing high quantum yield, strong photostability, and minimal background fluorescence in complex biological environments. Its far-red emission profile ensures low autofluorescence and improved tissue penetration, enabling high-contrast imaging and multiplexing with shorter-wavelength fluorophores. Supplied as a lyophilized powder, the conjugate is readily reconstituted in aqueous buffers, offering a robust and versatile tool for quantitative fluorescence analysis in both in vitro and in vivo systems.