Alexa Fluor™ 488 Antibody Labeling Kit

Catalog number:  A20181

Related applications:

Protein Labeling & Crosslinking

| Labeling Chemistry

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Molecular Probes® Alexa Fluor® Antibody Labeling Kits provide a convenient means to label small amounts of antibodies with Alexa Fluor® dyes (choice of 10 colors). This kit is optimized for labeling 100 µg of antibody per reaction with green fluorescent Alexa Fluor® 488. Comparably small amounts of other proteins (>40 kDa) can also be labeled.

The kit contains everything you need to perform five separate labeling reactions as well as to purify the resulting conjugates. Conjugates are ideal for multiple applications, including flow cytometry, fluorescent microscopy, immunohistochemistry, primary detection, ELISAs, immunocytochemistry, indirect FISH, and more.

Important Features of Alexa Fluor® 488 Antibody Labeling Kit:
• With an excitation and emission maximum of 494/519 nm, Alexa Fluor® 488 can be efficiently excited using a 488 nm Argon laser line and detected under standard FITC/Cy2® filters
• Labeled proteins typically ready to use typically in 90 min (~15 min hands-on time)
• Useful for labeling 100 µg of protein
• Optimized for small-scale labeling of any protein >40 kDa
• Purified using convenient spin filters
• Stabilizing proteins must be removed from the sample before labeling
• Includes detailed instructions for determining degree of labeling (DOL)

Better Results and Workflows with Primary labeled antibodies
A primary antibody directly labeled with a fluorophore often produces lower background fluorescence and less nonspecific binding. Further, multiple primary antibodies of the same isotype or derived from the same species can easily be used in the same experiment if they are directly labeled with compatible fluorophores.

Superior Alexa Fluor® Dyes
Compared to traditional dyes, Alexa Fluor® dyes are brighter, more photostable, and more pH resistant between pH 4 and 10. And generally when using Alexa Fluor® dyes, higher degrees of labeling can be achieved without intramolecular quenching. For details see Alexa Fluor® Dyes Spanning the Visible and Infrared Spectrum—Section 1.3.

Learn More About Protein and Antibody Labeling
We offer a wide selection of Molecular Probes® antibody and protein labeling kits to fit your starting material and your experimental setup. See Antibody Labeling from A to Z or use our Labeling Chemistry Selection Tool for other choices. To learn more about our various kits read Kits for Labeling Proteins and Nucleic Acids—Section 1.2 in the Molecular Probes® Handbook.

We'll Make a Custom Antibody Conjugate for You
If you can't find what you're looking for in our stocked list, we'll prepare a custom antibody conjugate for you. Our custom conjugation service is efficient and confidential, and we stand by the quality of our work. We are ISO 9001:2000 certified.

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


Detection Method: Fluorescent
Excitation/Emission: 495⁄519
Labeling Method: Conjugation-Based
Labeling Scale: 100 µg
Shipping Condition: Room Temperature
Color: Green
Emission: Visible
Label Type: Alexa Fluor Dyes
Labeling Target: Antibodies (General), Proteins (General)
Label or Dye: Alexa Fluor™ 488
Product Line: Alexa Fluor™

Contents & storage

Alexa Fluor® 488 Antibody Labeling Kit comes with 5 vials of reactive dye, sodium bicarbonate, purification resin, spin columns and collections tubes.

Store at 2-8°C, protected from light. Component A may be stored from -20 to 8°C.