Alexa Fluor Secondary Antibodies

We offer 18 different individual Invitrogen Alexa Fluor dyes and 4 Invitrogen Alexa Fluor tandem dyes conjugated to secondary antibodies. Invitrogen Alexa Fluor protein and antibody conjugates produce fluorescence outputs that exceed those of other spectrally similar fluorophore conjugates.

As the creators of the Alexa Fluor dye technology, we have extensive experience in providing fluorescent secondary antibodies that exhibit superior brightness and photostability and outperform conventional fluorescent secondary antibodies. With more than 30,000 publications, Alexa Fluor dyes have been successfully used over the last two decades of fluorescence imaging.

Alexa Fluor Plus Secondary Antibodies

Alexa Fluor Plus Secondary Antibodies

Need to detect and visualize low-abundance targets in rare or precious samples?

Compare to traditional Alexa Fluor secondary antibodies:

  • Higher signal-to-noise ratio
  • Lower cross-reactivity

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Alexa Fluor secondary antibody conjugates recommendation table

Alexa Fluor dye label Dye and conjugate features
Alexa Fluor 488
  • Bright, green fluorescent dye
  • Brightest, most photostable green dye for sensitive detection in live or fixed cells
  • 52 secondary antibody products available
Alexa Fluor 555
  • Bright, orange fluorescent dye
  • Recommended replacement for tetramethylrhodamine or Invitrogen Cy3 dye, exhibiting greater photostability
  • 24 secondary antibody products available
Alexa Fluor 594
  • Bright, red fluorescent dye
  • Recommended replacement for Invitrogen Texas Red dye, exhibiting brighter signal and excellent photostability
  • 40 secondary antibody products available
Alexa Fluor 647
  • Bright, far-red fluorescent dye
  • Ideal for imaging low-abundance targets, especially in fixed cells
  • 33 secondary antibody products available
Alexa Fluor 680
  • Bright, near-IR fluorescent dye
  • Ideal for multiplexing western blots
  • 20 secondary antibody products available
Alexa Fluor 790
  • Bright, near-IR fluorescent dye, the longest-wavelength Alexa Fluor dye available
  • Similar to indocyanine green (ICG) and IRDye™ 800 dyes
  • 11 secondary antibody products available

Alexa Fluor secondary antibodies by host and target species

Alexa Fluor secondary antibodies are available with a variety of host and target specificities, including goat, chicken, donkey, guinea pig, hamster, human, mouse, rabbit, sheep, and rat. The most popular host species for secondary antibodies is goat, while the most popular target species are anti-mouse and anti-rabbit because most primary antibodies are produced in these animals. Knowing that antibodies of these host and target specificities are most common, we offer goat anti-mouse and goat anti-rabbit secondary antibodies conjugated to all of the Alexa Fluor dyes. We also offer Alexa Fluor conjugated secondary antibodies with other host and target species combinations.

Secondary Antibodies by Target Species
Summary of Alexa Fluor secondary antibodies by host/target species and excitation spectrum. To view individual products, filter search results after navigating to one of the Alexa Fluor conjugate links presented in the previous tables, or visit Secondary Antibodies by Target Species.

Alexa Fluor secondary antibodies for imaging and western blotting

Alexa Fluor secondary antibodies can be used in a variety of cell analysis and protein analysis applications. The most popular applications are imaging and fluorescent western blotting.

Cell imaging allows scientists to see inside a cell and better understand and predict cell health and function. Cell imaging comes in different formats, including immunohistochemistry (IHC), immunocytochemistry (ICC), and immunofluorescence (IF). We have Alexa Fluor secondary antibodies that will work in each of these applications. For information about using secondary antibodies for immunolabeling, see our page on immunolabeling using secondary antibodies.

Muntjac skin cell labeled in three different colors using an Alexa Fluor secondary antibody. Golgi bodies in a muntjac skin cell were labeled with anti–golgin-97 monoclonal antibody (Cat. No. A-21270) and visualized with green-fluorescent Invitrogen Alexa Fluor 488 goat anti–mouse IgG1 antibody (Cat. No. A-21121). Filamentous actin was labeled with Invitrogen Alexa Fluor 680 phalloidin (Cat. No. A22286, pseudocolored purple). Nuclei were stained with blue-fluorescent DAPI (Cat. No. D1306, D3571, D21490).

Fluorescent western blotting is growing in popularity because of its time savings and multiplex detection capabilities compared to traditional western blotting methods. The wide range of Alexa Fluor secondary antibodies provides conjugates with non-overlapping spectra to enable multiplex analysis. Multiple targets can be detected independently in the same lane and blot with clear distinction between colors.

Simultaneous detection of GLUT4 and GAPDH using Alexa Fluor secondary antibodies

Simultaneous detection of GLUT4 and GAPDH using Alexa Fluor secondary antibodies. GLUT4 and GAPDH were detected simultaneously in 3T3-L1 adipocyte lysates using mouse anti-GAPDH and rabbit anti-GLUT4 with Alexa Fluor 680 goat anti–mouse IgG (Cat. No. A-21058) and Invitrogen Alexa Fluor 790 goat anti–rabbit IgG Cat. No. A11369). Single-color images were merged to visualize both proteins. GAPDH bands are shown in red, and GLUT4 bands are pseudocolored green.