[Dot immunoassay with colloidal silver particles as a marker of specific antigen for testing human sera for...

Whether the dot immunoassay is suitable for the detection of Brucella antibodies in human sera by using a colloidal silver-labeled Brucella specific antigen as a diagnostic tool is assessed. The antigen was the B. abortus 19BA protein polysaccharide complex isolated by Brucella acetic acid hydrolysis. The dot immunoassay is easy-to-use, cost-effective, highly sensitive, and therefore of more informative value in detecting Brucella antigens than routine serological tests (Huddleson test, Wright agglutination test, passive hemagglutination test, long-term complement fixation test, and Coombs test). It requires no use of expensive equipment and reagents.