Development of a Biomimetic Enzyme-linked Immunosorbent Assay Method for the Determination of Methimazole in Urine Sample

A fast and direct competitive biomimetic enzyme-linked immunosorbent assay (BELISA) method was developed for the determination of methimazole (MMZ) in urine sample based on a molecularly imprinted film as an artificial antibody. This is the first example to monitor methimazole with a direct competitive biomimetic enzyme-linked immunosorbent assay (BELISA) method. The imprinted film was directly synthesized on the well surface of MaxiSorp polystyrene 96-well plate and characterized. The results showed that it exhibited an antibody-like binding ability, rapid adsorption speed, high stability, which was particularly advantageous and suitable for BELISA development. The BELISA method established in this paper had a higher selectivity for MMZ than for the structurally related compounds and the IC50 (calculated as the concentration giving 50% inhibition of color development) and the detection limit values under optimized experimental conditions were 70 +/- 4 mu g L-1 and 0.9 +/- 0.04 mu g L-1, respectively. The method was applied to the determination of MMZ in spiked urine sample with excellent recoveries ranging from 90% to 95%, and the imprinted film was able to be reused for 20 times without loss of sensitivity. The results obtained by BELISA correlated well with that obtained by the high performance liquid chromatography (HPLC) method.