VMC 221: Veterinary Immunology and Serology (1+1)

GEL DIFFUSION TEST/AGAR GEL IMMUNODIFFUSION TESTS(AGID)/AGAR GEL PRECIPITATION TESTS [AGPT]

• A simple method of demonstrating precipitation of antigen by antibody is immunodiffusion or gel diffusion.
• Addition of agar to one or both reagents or between the reagents retards the rate of diffusion and permits formation of multiple distinct lines of precipitate if several antigenic substances and their antibodies are present.
• The forms of precipitation in gel commonly used are
  • Single diffusion in one dimension (Oudin test)
  • Double diffusion in one dimension (Oakley – Fulthorpe test)
  • Single diffusion in two dimension (Mancini test)
  • Double diffusion in two dimension (Ouchterlony test)