With more than 6000 primary antibodies available, the addition of the NorthernLights line of fluorescent secondary antibodies makes R&D Systems your total source for immunofluorescence reagents.

NorthernLights are bright and fade-resistant antibodies recognizing mouse, goat, and rabbit IgG. Like all R&D Systems antibodies, NorthernLights antibody conjugates are highly specific and deliver a high signal-to-noise ratio. Also available are streptavidin conjugates for labeling biotinylated cells and tissues. Their spectral properties are similar to several widely used fluorochromes, and are therefore suitable for use with common filter sets and/or lasers (Table). These secondary antibodies are available with three distinct excitation and emission maxima, making them ideal for multi-color fluorescence microscopy (Figure 1). NorthernLights secondary antibodies are stable when exposed to alcohols and xylene, as well as DPX mounting medium. They have been tested for their suitability in both immunochemistry and flow cytometry (Figure 2 and 3).

Figure 1. Rat cortical stem cell differentiation was monitored using multi-color immunocytochemistry. Neural progenitors were labeled with R&D Systems goat anti-rat nestin polyclonal antibody (Catalog # AF2736) and stained with R&D Systems donkey anti-goat NorthernLights-493 secondary antibody (Catalog # NL003; green). Differentiated neurons were labeled with R&D Systems neuron-specific mouse anti-beta-III tubulin monoclonal antibody (TuJ1; Catalog # MAB1195) and stained using R&D Systems donkey anti-mouse NorthernLights-557 secondary antibody (Catalog # NL007; red). Nuclei were stained with DAPI (blue).	Figure 2. Glucagon is selectively expressed by some cells of the mouse pancreatic beta cell line beta-TC6. Glucagon was detected using R&D Systems anti-human/mouse monoclonal antibody and cells were stained with R&D Systems NorthernLights-557 secondary antibody (Catalog # NL007; red). The nuclei were counterstained with DAPI (blue).
Figure 3. Jurkat T cells were fixed, permeabilized, and incubated with R&D Systems anti-human Akt1 monoclonal antibody (Catalog # MAB17751). Cells were then stained with R&D Systems anti-mouse IgG NorthernLights-637 (Catalog # NL008; red histogram). Control stain­ing was done by incubating cells in R&D Systems IgG1 isotype control monoclonal antibody (Catalog # MAB002), followed by the staining with NorthernLights-637 (black histogram).