A mini-stirrer for preparing antigen/adjuvant emulsions

For immunization of animals with antigenic substances, the antigen is usually incorporated into an adjuvant to potentiate the immune response. One of the commonly used adjuvants is Freund's incomplete adjuvant (FIA), containing mineral oil which when mixed thoroughly with the antigen in phosphate-buffered saline produces a stable, thick and creamy water-in-oil emulsion, which provides sustained release of the antigen from a depot at the inoculation site, essential for maximizing the immune response. However, stable antigen/water-in-oil emulsion are difficult to prepare. We describe a method for preparing antigen/FIA emulsions in syringes with minimal loss since the same syringe is used for inoculation.