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

DOT ELISA

• Similar to the plate ELISAs, but the solid phase to which antigen is bound is the nitrocellulose membrane (usually) and the chromogenic substrate used is DAB which forms an insoluble product.
• Hence in positive cases a brown dot is obtained at place of antigen deposition.
• The advantage of dot ELISA over other ELISAs is that the color reaction can be read visually without sophisticated ELISA readers.
• The test is also easy to perform and can be done in the field.
•  The results i.e. dots can be stored for retrospective analysis.