Isotype Controls

Isotype controls are important negative controls and very important to reduce the overall false-positive results. Using an appropriate isotype control is critical for scientific research. It can help distinguish non-specific background stainings from specific antibody detection. Therefore, it can confirm staining results observed in immunoassays, such as flow cytometry (FACS), enzyme-linked immunosorbent assay (ELISA), western blot (WB), immunoprecipitation (IP), immunofluorescence (IF), and immunohistochemistry (IHC). Creative Biolabs provides a complete range of isotype controls covering common species, and with a variety of conjugates, such as Alexa Fluor^® dyes, horseradish peroxidase (HRP), biotin, phycoerythrin (PE), fluorescein isothiocyanate (FITC), agarose, and other formats.

Introduction of Isotype Control

Isotype controls are antibodies that share similar properties with the primary antibodies but cannot achieve specific antibody-antigen binding. Used together with primary antibodies, negative controls help determine the existence of non-specific background staining. Generally, the isotype control should be negative when the background signal is unaffected by the Fc receptor binding, reactive epitopes, and endogenous enzymes.

Importance of Using Isotype Control

Non-specific binding to primary antibodies is typically caused by: 1) Non-specific Fc receptor binding to cells. 2) Cell autofluorescence. 3) Non-specific antibody interactions with cellular proteins. Using the right isotype control can reduce background staining, allowing interpretation of the true signal. This allows a successful detection of target molecules. Including negative controls is, therefore, very important to help reduce the risk of false-positive results.

How to Choose a Suitable Isotype Control?

• Use an isotype control that originates from the same host species as the primary antibody.
• Use an isotype control that shares the same isotype and subclass as the primary antibody.
• Use an isotype control that exhibits the same conjugation format as the primary antibody.
• Use an isotype control that has the same concentration as the primary antibody.

Creative Biolabs provides a comprehensive range of isotype controls formulated for both in vivo and in vitro applications. Advantages of our isotype controls including but not limited to:

• High purity (QC tested by SDS-PAGE and SEC-HPLC)
• Ultra-low endotoxin levels (≤0.1 EU/mg)
• Pathogen free
• Low protein aggregation

For more detailed information, please feel free to contact us or send us an inquiry directly.

Reference

1. Keeney, M.; et al. Isotype controls in the analysis of lymphocytes and CD34+ stem and progenitor cells by flow cytometry-time to let go!. Cytometry (Communications in Clinical Cytometry). 1998, 34:280-3.