Enzyme Immunoassays for Analysis of Pesticides in Water and Food

Andren Dankwardt, Bertold Hock

Technical University of München, Department of Botany, D-85350 Freising, Germany

Article history:
Received July 15, 1997
Accepted September 30, 1997

Key words:
enzyme immunoassays, antibodies, pesticides, cross-reactivity, matrix effects, water analysis, food analysis,

Summary:
Enzyme immunoassays offer reliable tools for the analysis of pesticides in water and food. They profit from the unique properties of antibodies as binding proteins with respect to their selectivity and affinity towards the ligands such as pesticides. Both polyclonal and monoclonal antibodies can be used to develop sensitive immunoassays. The choice of antibody depends on the scope and intention of antibody application. The structure of the immunoconjugate is an important factor for the development of sensitive and selective antibodies. For the analysis of small molecules such as pesticides usually competitive immunoassays with phase separation are applied. Optimization of the assay can be achieved by varying the test system (e.g. heterologous instead of homologous tracer system) or applying amplification methods. Common error sources, especially cross-reactivities and matrix effects, are discussed. Representative examples are given for the application of enzyme immunoassays for the determination of pesticides in water and food samples. New techniques such as immunoafinity chromatography, coupling of liquid chromatography with immunoassays and immunosensors are discussed. An outlook is given on mullianalyle detection and the potential of recombinant antibodies in water and food analysis.