Strengths and limitations of immunoassays for effective and efficient use for pesticide analysis in water samples: A review

Immunoassay techniques provide a simple, powerful and inexpensive method for pesticide analysis. However, the acceptance of immunoassays is dependent on the demonstration of quality and validity compared to more traditional techniques. In this review, primarily, the knowledge and the fundamentals of immunoassay methods are given in order to make good use of immunoassays, especially of ELISA tests. Special attention is given to a better understanding of the high selectivity and sensitivity which is attained for some immunoassays and not for others. It is also explained why some immunoassays are a quantitative method whereas others can only be used as a screening method. The cross-reactivity process, the effect of the sample matrix and the data interpretation are illustrated by numerous examples from the literature. Other formats, especially flow-injection immunoassays, dipstick immunoassay and liposome-amplified immunoassays are presented. Quality assurance and guidelines for validation and use are given.