The authors examined the possibility of replacing immunoperoxidase con
jugates with silver sol (mean diameter of particles 9 nm) adsorption-b
ound to antispecies IgG in solid-phase enzyme immunoassay in microtitr
ation plates. Experiments with commercial test systems Antigen and Rec
ombitest-antiHIV-1,2 manufactured by the Vektor State Research Center
of Virology and Biotechnology, Ministry of Health and Medical Industry
of the Russian Federation, showed that the sensitivity of detecting a
nti-HIV with silver immunosols and boosting of the signal with physica
l development was no less sensitive than standard EIA with immunoperox
idase conjugate. Preparation of silver immunosols is simple, easily re
producible, and is based on sparing and economic use of immunoreagents
.