Jackson Immuno Research Inc.
specializing in secondary antibodies and conjugates

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Fluorescent Dyes

Brilliant Violet™
421 & 480

  • Combine with AF488, RR-X, & AF647 for 5-color imaging
  • Compatible with commonly used filter sets
  • Switch nuclear stain from DAPI to DRAQ5™ for additional labeling options

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Whole IgG Affinity-Purified Secondary Antibodies

"Without question, I can always turn to Jackson ImmunoResearch secondary antibodies for ECL detection of any primary antibody! They produce great signal at low dilutions."

W Thompson, OSHU

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Monovalent Fab Fragments for Double Labeling - Example A

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Fab Fragments for Blocking and Double Labeling of Primary Antibodies from the Same Host Species

Example A. Use of conjugated Fab fragments for labeling and blocking.

figure 1

figure 1 

  1. Incubate with the first primary antibody,in this example Rabbit Anti-Antigen X. Wash.

  2. Incubate with excess Probe I-conjugated secondary antibody, in this example Alexa Fluor® 488-Fab fragment Goat Anti-Rabbit IgG (H+L). Wash.

  3. Incubate with the second primary antibody, Rabbit Anti-Antigen Y, followed by Probe II-conjugated secondary antibody, in this example Rhodamine Red-X-Goat Anti-Rabbit IgG (H+L). Wash.

Caution: This protocol may be subject to the following problems:

(1) Example A may require a high concentration of conjugated Fab to achieve effective blocking of the first primary antibody. If this results in unacceptable background, try a lower concentration of the conjugated Fab, followed by further blocking with unconjugated Fab.

(2) If small aggregates of conjugated Fab are bound to the first primary antibody, they may act as divalent or polyvalent antibodies and capture some of the second primary antibodies, which would result in overlapping detection of antigens.

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