Enzyme-linked immunosorbent assay (ELISA) for sole (Solea vulgaris) vitellogenin

1. 1. A specific and simple immunoassay for the sole (Solea vulgaris) vitellogenin (Vg) is described. This assay was developed using an antiserum to plasmatic Vg. 2. 2. The assay is based upon the competition between soluble Vg and Vg adsorbed on microtiter plates, for the rabbit anti-Vg antibody binding sites. 3. 3. The adsorbed Vg-antibody complexes are then revealed using the peroxidase-antiperoxidase technique. 4. 4. Following the revelation of the peroxidase activity by an appropriate chromogen, the resulting absorbance values are measured. The intensity of the reaction is proportional to the antibody linked to the adsorbed Vg. This assay can be performed in 6 hr. 5. 5. In our conditions a sensitivity range of 2.5–320 ng gave 90–10% of binding. Near 50% binding (20 ng) the intra-assay variation coefficient (CV) was 4.5% (n = 20) and the inter-assay CV was 7.5% (n = 12). 6. 6. This assay has been used for the quantitation of Vg in various biological samples. 7. 7. This enzyme immunoassay methodology could be a useful alternative to the use of radioactive substances.