Organometallic Complexes Used as Enzyme Substrates

This is an immunoassay in which competition for binding to the specific antibodies, attached to magnetic beads, is between the analyte to be assayed and the analyte attached to an enzyme, alkaline phosphatase (AP) (Fig. 8.19). 

This is then concentrated in the polyanionic Nafion film coating the electrode and quantified by cyclic voltammetry as shown in Fig. 8.19. The feasibility of this immunoassay has been demonstrated for a herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D) with a detection limit of 0.01 pg [89]. 

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