Development of solid-phase immunoassay using chemiluminescent IgG conjugates

Solid-phase luminescent immunoassay (LIA) was studied using mainly aminobutyl-ethylisoluminol-IgG conjugates. Different solid-phase supports such as immunobeads, polystyrene balls and tubes gave comparable results although tubes were preferred in most of the assays because of the better linearity and reproducibility obtained and their ease of handling. The properties of the conjugates were tested using both direct and sandwich LIA. Direct LIAs performed using sheep-anti-rabbit IgG coated balls provided information on the antigenicity of the conjugates while the sandwich LIA was the actual working system. A sensitivity of 1 ng was obtained in this system. The stability, easy use, safe handling and low cost of the conjugates coupled with a short assay time make this luminescent system a potential alternative to RIA.