[Development and optimization of immunoassays for the detection of botulinum toxins]

Monoparametric immunoassay tests for detecting botulinum toxins types A and B and multiparametric assays for simultaneous detection of botulinum toxins type A and B have been developed. It is shown that the sensitivity of assays is affected by the size of nanoparticles of colloidal gold used as a marker of antibodies, load intensity of antibodies of colloidal gold in conjugates, the type of analytical membranes, as well as the chemical composition of buffer solutions used for the storage of conjugates and immunoassay analysis. The detection limit of monoparametric immunoassay tests is 0.5 ng/ml; that of multiparametric assays, 5.0 ng/ml. The developed immunoassay can be used for rapid assay of product quality, for grade control of botulinum toxins in pharmaceuticals, and environmental monitoring.