Cy3 Fluorescent Conjugates

Our extensive line of CyDye conjugates is available across a range of animal species, including human, mouse, rabbit and rat antibodies, as well as other animal species and streptavidin. They are affinity purified and in some cases further adsorbed to minimize cross-reactivity between animal species or shared reactivity with other immunoglobulin classes. KPL mouse antibodies are cross-adsorbed against human serum to minimize cross-reactivity. Anti-heavy and light chain antibodies provide species-specific detection of the IgG class. Antibodies directed against heavy chains react specifically with the heavy chain in the product name; light chain reactivity has been removed. F(ab’)2  fragment antibodies are also available for assays requiring extremely low background levels and absence of F(c)-mediated binding.

Cy Dyes offer intense fluorescence when coupled KPL’s affinity purified antibodies and streptavidin. The cyanine dye is a water-soluble, orange fluorescing compound that produces an intense signal. The sensitivity and reproducibility of KPL antibodies combined with the brightness of Cy3 dyes produce an exceptional set of conjugates ideal for multiple labeling experiments.  Dye/protein ratios have been established to ensure optimal fluorescence with minimal background.

Human epithelial tissue detected with monoclonal Mouse anti-Epithelial Membrane Antigen (Clone E29) and KPL Cy3-labeled goat anti-mouse antibody (part #072-01-18-06) red. DAPI nuclear fluorescent counterstain (part #71-03-01) blue.  200x magnification

Cyanine Dyes
Cyanine dyes are excellent alternatives to many other fluorescein dyes as they are brighter and offer greater photostability. Cy3 is excited maximally at 550 nm and emits maximally in the red end of the spectrum at 570 nm. Cy3 is ideally used in visual color applications and can be excited by mercury arc lamps and detected with TRITC filter sets.

     ------- Excitation

     _____ Emission

Cy3 and Cy5 Conjugates are Ideal for Multiple Labeling 
KPL also offers Cy5 conjugates which are excited maximally at 650 nm and emit maximally at 670 nm in the red end of the spectrum. Instrumentation is able to easily distinguish between the two signals when one antigen is labeled with Cy3 and the other with Cy5.  A confocal microscope equipped with the appropriate laser for excitation and a far-red detector enables double labeling with Cy3 and Cy5.

Excellent Performance
KPL Cy3-labeled antibodies produce brighter fluorescence than those of other suppliers as demonstrated below: