Alexa Fluor^® 647 conjugated anti-horse primary antibodies are far-red fluorescent immunoreagents designed for multiplexing and low-background detection of equine antigens. Produced by immunizing hosts such as goat or rabbit with purified horse immunoglobulins, these antibodies are affinity-purified and covalently conjugated to Alexa Fluor^® 647, a small-molecule fluorophore with excitation/emission maxima of 650/665 nm. This fluorophore exhibits exceptional photostability, a high quantum yield (approximately 0.33), and stable fluorescence across a broad pH range (pH 4–10), outperforming traditional far-red dyes such as Cy^®5. Its far-red emission spectrum minimizes spectral overlap with fluorophores such as FITC and PE while significantly reducing tissue and fixative autofluorescence, making it particularly well suited for multicolor fluorescence applications.

Applications

Alexa Fluor^® 647 conjugates are widely used in flow cytometry and fluorescence-activated cell sorting (FACS), where their high brightness enables the sensitive detection of low-abundance equine surface markers, including CD4, CD8, and MHC class II molecules. In confocal and super-resolution microscopy, their excellent photostability supports extended image acquisition and z-stack imaging with minimal photobleaching. These conjugates are also compatible with near-infrared imaging platforms for in vivo studies, multiplex bead-based assays for cytokine profiling, and fluorescent western blotting, where they provide direct fluorescence detection without enzymatic amplification. Typical working dilutions range from 1:100 to 1:2,000 depending on the experimental application. These products are intended for research use only and are not designed for diagnostic procedures.