Isotype Controls

Isotype controls are used to confirm that the given signal is specific and not a result of non-specific Fc receptor binding or other protein interactions of the primary antibody.

Isotype control antibodies have no relevant specificity for the cells in question but with all the non-specific characteristics of the antibody used in the experiment. Isotype controls are considered one of the possible negative controls for your experiment and are most commonly used in flow cytometry and immunohistochemistry or immunocytochemistry.

An isotype control should be of the same species and isotype, used at the same concentration and conjugated to the same label as the specific primary antibody used in the experiment.

Therefore, OriGene provides a wide range of isotype controls with different conjugates.

How to best select the correct isotype control

After you have used our search bar, you can use our filters to narrow down:

  1. The correct product type (choose product type "Isotype Controls" as a subcategory of "Antibodies")
  2. The host you need for your isotype control (same host as your primary antibody)
  3. The isotype you need (same isotype as your primary antibody)
  4. The conjugate (or unconjugated) you need (same conjugate as your primary antibody)

Discover OriGene's isotype controls

You can find pre-filtered isotype controls for Mouse/Rat/Hamster primary antibodies here:


One example of the use of an isotype control can bee seen here. The Flow Cytometry signal can be clearly distinguished between the unspecific signal from the isotype control and the specific signal of the LGR5 antibody binding to its target.

HT29 cells are fixed with 2% formaldehyde for 20 min at RT, then stained with PE-labeled 2A2 anti-LGR5 antibody or PE labeled isotype control.
Black line: PE-conjugated isotope control.
Red line: anti-Lgr5-PE, Cat.No. TA400001.