Freund's Complete Adjuvant

Freund's Complete Adjuvant (FCA/CFA) is a commonly used immunological adjuvant prepared according to the classic method using low-endotoxin, high-purity oils such as paraffin oil that are not metabolized by animals, along with inactivated Mycobacterium bovis BCG. It contains no preservatives and is widely used for animal immunization to produce antibodies.

Freund's Adjuvant was invented by Jules Freund in the 20 century, during the 40 decade. It is generally considered the most commonly used immunological adjuvant in animal experiments and is frequently employed for antibody production through animal immunization. Freund's Adjuvant enables sustained release of antigens while non-specifically enhancing the host's specific immune response to those antigens, thereby boosting their immunogenicity or altering the type of immune reaction. While it enhances immune responses, it can also cause local adverse reactions such as granuloma formation and inflammation at the injection site. There are two types: Freund's Incomplete Adjuvant (FICA/FIA/IFA), which does not contain Mycobacterium tuberculosis, and Freund's Complete Adjuvant (FCA/CFA), which does.

Incomplete Freund's adjuvant consists mainly of oil and an emulsifier. When mixed with an antigen, it forms a water-in-oil emulsion that enables slow antigen release, stimulating high-titer, long-lasting antibody production. Complete Freund's adjuvant is incomplete Freund's adjuvant supplemented with Mycobacterium tuberculosis. It elicits a stronger immune response and is typically used for primary immunization. Incomplete Freund's adjuvant is generally used for booster immunizations following the primary dose to avoid the side effects associated with Complete Freund's adjuvant while promoting high-antibody titers.

The mechanism of action of adjuvants is not fully understood. Adjuvants may increase the surface area available for antigen presentation, making it easier for macrophages to engulf; they may prolong antigen retention in the body, increasing opportunities for contact with immune cells; they may enhance the ability of antigen-presenting cells to process and present antigens; or they may induce inflammation at the injection site and in local lymph nodes, thereby promoting the proliferation of immune cells. All these mechanisms can potentially improve antibody titers following both primary and booster immunizations.

Save conditions:

Store in a cool, dark place at 4°C. Valid for at least one year. Do not freeze!

Important Notes:

Store this product protected from light at 4°C. Do not freeze at -20°C or below.

This product may form a small amount of Mycobacterium tuberculosis sediment after prolonged standing. Shake well before use to fully resuspend the sediment prior to application.

If the antigen contains glycerol or urea, emulsification efficiency may decrease or emulsification may fail entirely.

This product is intended for scientific research by professionals only. It must not be used for clinical diagnosis or treatment, in food or drugs, or stored in residential homes.

For your safety and health, please wear a lab coat and disposable gloves when operating.