An enzyme-linked molecularly imprinted sorbent assay

Based on a molecularly imprinted polymer, a competitive binding assay analogous to competitive enzyme immunoassay has been developed. The assay is specific for the herbicide 2,4-dichlorophenoxyacetic acid and uses, for the first time, an enzyme-labelled conjugate as a tracer. The label tobacco peroxidase allowed for colorimetric and chemiluminescence detection. The molecularly imprinted polymer was synthesised in the form of microspheres by precipitation polymerisation. The polymer efficiently and selectively bound the analyte in aqueous solution. Calibration curves were obtained corresponding to analyte concentrations ranging from 40-600 mu g mL(-1) for the colorimetric assay, and from 1-200 mu g mL(-1) for chemiluminescence assay.