An enzyme-linked molecularly imprinted sorbent assay

Based on a molecularly imprinted polymer, a competitive binding assay analo gous to competitive enzyme immunoassay has been developed. The assay is spe cific for the herbicide 2,4-dichlorophenoxyacetic acid and uses, for the fi rst time, an enzyme-labelled conjugate as a tracer. The label tobacco perox idase allowed for colorimetric and chemiluminescence detection. The molecul arly imprinted polymer was synthesised in the form of microspheres by preci pitation 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 colorime tric assay, and from 1-200 mu g mL(-1) for chemiluminescence assay.