Immunoassays in the Analysis of Water

Abstract

Radioimmunoassays were first described some 25 years ago and have since been widely applied. In general, immunoassays depend on the principle of competitive binding or saturation analysis. More recently, non isotopic techniques have been utilised in attempts to overcome some of the disadvantages associated with the use of radioactivity.

Immunoassays are simple to perform, cost effective and universally applicable to molecules greater than 150 daltons mol. wt. Undoubtedly, their main advantage lies in the exquisite sensitivity that can be achieved (10^?9 -10^?10molar). Immunoassays are ideally suited to the quantitation of analytes in water, especially as sensitivity can be further increased by a simple concentration step.

The specificity of immunoassays depends on the particular antiserum used. Group specificity, useful for screening procedures, is readily achieved. With a careful choice of immunogen antisera with absolute specificity is also possible.

The potential for immunoassays in water analysis has not yet been realised although few problems should arise in adapting existing assays or in developing new assays of direct relevance to the water industry.