Discs of polyvinyl alcohol cross-linked with glutaraldehyde
were synthesized under acid catalysis (H2SO4). Then, the
antigen F1 purified from Yersinia pestis was covalently linked
to this modified polymer. Afterwards, an enzyme-linked
immunosorbent assay (ELISA) was established for the diagnosis
of plague in rabbit and human. The best conditions for the
method were achieved by using 1.3 ug of F1 prepared in 0.067 M
phosphate buffer, pH 7.2, containing 1 M NaCl (PBS); anti-IgG
peroxidase conjugate diluted 6,000 times and as a blocking
agent 3% w/v skim milk in PBS. The titration of positive
rabbit serum according to this procedure detected antibody
concentrations up to 1:12,800 times. The present method, the
conventional ELISA and passive haemagglutination assay are
compared.