iFluor® 647–dextran conjugate (average molecular weight ~10,000 Da) is a hydrophilic fluorescent probe composed of a 10 kDa dextran polymer covalently labeled with iFluor® 647, a far-red-emitting dye with excitation and emission maxima at approximately 656 nm and 670 nm, respectively. The relatively low molecular weight of the dextran backbone supports efficient cellular uptake and intracellular diffusion, making this conjugate particularly suitable for applications such as endocytosis tracking, fluid-phase uptake assays, and vesicular transport studies.

iFluor® 647 exhibits spectral characteristics comparable to Alexa Fluor® 647 and Cy5, offering high fluorescence quantum yield, excellent photostability, and minimal spectral overlap with visible-range fluorophores. Its far-red emission profile provides low background fluorescence and enhanced penetration in tissue imaging, enabling multiplexing with other fluorophores in multi-color flow cytometry and microscopy applications. The conjugate is supplied as a lyophilized powder and reconstitutes readily in aqueous buffers, providing a reliable and high-sensitivity tracer for both live-cell and fixed-sample experiments requiring detection in the far-red spectral range.