Invitrogen Alexa Fluor protein and antibody conjugates produce fluorescence outputs that exceed those of other spectrally similar fluorophore conjugates and do not photobleach as easily as classic fluorescent secondary antibodies. With more than 80,000 publications, our Alexa Fluor secondary antibodies are reliable research tools. Browse our comprehensive portfolio of Alexa Fluor and Alexa Fluor Plus secondary antibodies for fluorescent detection of primary antibodies in a wide range of applications, such as cell imaging, flow cytometry, and western blotting.


Alexa Fluor secondary antibody product information

Alexa Fluor secondary antibodies have been tested extensively to help ensure optimal performance. Alexa Fluor Plus secondary antibodies have been optimized further to enable better detection of low-abundance targets and are excellent for use in rare or precious samples. 

 Alexa Fluor Secondary AntibodiesAlexa Fluor Plus Secondary Antibodies
UseDesigned for use in a variety of cell analysis and protein analysis applications to detect targets at varying expression levels
  • Designed to help detect and visualize low-abundance targets in rare or precious samples
  • Optimized for excellent multiplexing experiments
Applications
  • Immunohistochemistry 
  • Immunocytochemistry 
  • Immunofluorescence
  • Western blot 
  • Multiplex immunocytochemistry 
  • Multiplex immunohistochemistry 
  • Multiplex western blot
Key product attributes
  • Improved brightness, pH insensitivity, and photostability compared to classic dyes
  • Broad spectral range coverage
  • Higher signal-to-noise ratio than traditional Alexa Fluor secondary antibodies
  • Up to 4.2x higher signal to noise in immunohistochemistry/immunocytochemistry 
  • Up to 5.8x higher signal to noise in fluorescent western blot
  • Lower cross-reactivity compared to traditional Alexa Fluor secondary antibodies
Targets species available
  • Mouse
  • Rabbit
  • Goat
  • Rat
  • Human
  • Hamster
  • Chicken
  • Sheep
  • Guinea pig
  • Mouse
  • Rabbit
  • Goat
  • Rat
  • Human
  • Chicken
Fluorophores available18 Alexa Fluor dyes available7 Alexa Fluor Plus dyes available
Antibody formats available
  • Whole IgG
  • F(ab’)2 Fragment
  • F(ab) Fragment
  • VHH 
  • Whole IgG
  • F(ab’)2 Fragment
Mountant compatibilityMost standard fixatives. See the selection guide: Mounting Media and Antifades
Recommended:


Alexa Fluor and Alexa Fluor Plus selection guide

Alexa Fluor conjugate
(click for dye information)
Excitation/emission (in nm)See available secondary antibodies
Alexa Fluor 350 Dye343/441Alexa Fluor 350 secondary antibodies
Alexa Fluor 405 Dye401/422Alexa Fluor 405 secondary antibodies
Alexa Fluor Plus 405 Dye404/455Alexa Fluor Plus 405 secondary antibodies
Alexa Fluor 430 Dye431/540Alexa Fluor 430 secondary antibodies
Alexa Fluor 488 Dye499/520Alexa Fluor 488 secondary antibodies
Alexa Fluor Plus 488 Dye493/518Alexa Fluor Plus 488 secondary antibodies
Alexa Fluor 514 Dye518/543Alexa Fluor 514 secondary antibodies
Alexa Fluor 532 Dye534/553Alexa Fluor 532 secondary antibodies
Alexa Fluor 546 Dye561/572Alexa Fluor 546 secondary antibodies
Alexa Fluor 555 Dye553/568Alexa Fluor 555 secondary antibodies
Alexa Fluor Plus 555 Dye558/572Alexa Fluor Plus 555 secondary antibodies
Alexa Fluor 568 Dye579/603Alexa Fluor 568 secondary antibodies
Alexa Fluor 594 Dye590/618Alexa Fluor 594 secondary antibodies
Alexa Fluor Plus 594 Dye590/618Alexa Fluor Plus 594 secondary antibodies
Alexa Fluor 633 Dye631/650Alexa Fluor 633 secondary antibodies
Alexa Fluor 635 Dye633/648Alexa Fluor 635 secondary antibodies
Alexa Fluor 647 Dye650/671Alexa Fluor 647 secondary antibodies
Alexa Fluor Plus 647 Dye658/675Alexa Fluor Plus 647 secondary antibodies
Alexa Fluor 660 Dye663/691Alexa Fluor 660 secondary antibodies
Alexa Fluor 680 Dye681/704Alexa Fluor 680 secondary antibodies
Alexa Fluor Plus 680 Dye687/704Alexa Fluor Plus 680 secondary antibodies
Alexa Fluor 700 Dye696/719Alexa Fluor 700 secondary antibodies
Alexa Fluor 750 Dye752/776Alexa Fluor 750 secondary antibodies
Alexa Fluor Plus 800 Dye789/794Alexa Fluor Plus 800 secondary antibodies


Alexa Fluor secondary antibody formats

Our Alexa Fluor and Alexa Fluor Plus conjugated secondary antibodies are now available in a variety of formats, each offering unique benefits. 

F(ab) and F(ab’)2 fragment Alexa Fluor secondary antibodies

We offer F(ab) and F(ab’)2 fragment secondary antibodies with various Alexa Fluor conjugate options. These secondary antibody fragments are cross-adsorbed to increase sensitivity, reduce background staining, and offer several benefits over whole IgG antibodies. Because of their smaller size they can more easily penetrate complex tissue models compared to whole IgG molecules, potentially leading to more antigen binding capability. This property, combined with Alexa Fluor and Alexa Fluor Plus conjugation, makes these molecules valuable staining tools in immunohistochemistry and immunofluorescent experiments.

Superclonal recombinant Alexa Fluor secondary antibodies

Superclonal recombinant secondary antibodies provide polyclonal sensitivity with monoclonal specificity in a recombinant format. Now available with a variety of Alexa Fluor and Alexa Fluor Plus conjugates, our Superclonal recombinant secondary antibodies help ensure reliable results with their lot-to-lot consistency. 

Alexa Fluor ReadyProbes Secondary Antibodies

ReadyProbes secondary antibodies are conjugated with bright and photostable Alexa Fluor 488 and Alexa Fluor 594 dyes to offer convenient and robust labeling. These Alexa Fluor secondary antibodies recognize IgG heavy chains and all classes of immunoglobulin light chains from either mouse or rabbit. Like other ReadyProbes reagents, these secondary antibodies are provided in a convenient dropper bottle format. No pipetting or dilutions are required.

Rabbit IgG (H+L) Cross-Adsorbed Secondary Antibody in ICC/IF. CAKI cells were plated on coverslips overnight. Then, cells were fixed and permeabilized. Following suppression of background binding using Image-iT FX Signal enhancer (Cat. No. R37107), peroxisomes were labeled using a rabbit anti-PMP70 antibody followed by detection with Goat anti-Rabbit IgG (H+L) Cross-Adsorbed ReadyProbes Secondary Antibody, Alexa Fluor 488 (Cat. No. R37116). Cells were washed three times in dPBS and nuclei were stained with NucBlue Fixed Cell ReadyProbes Reagent (DAPI) (Cat. No. R37606) and actin was visualized with ActinRed 555 ReadyProbes Reagent (Rhodamine phalloidin) (Cat. No. R37112). Images were acquired on the EVOS FL Auto imaging system using a 40x coverslip-corrected objective.


Alexa Fluor secondary antibody resources


Related instruments


Related pages

Stylesheet for Classic Wide Template adjustments

For Research Use Only. Not for use in diagnostic procedures.