| A detailed review on the synthesis, characterization and application of molecularly imprinted polymers, ion selective electrode (ISE) and electrochemiluminescence (ECL) was carried out. Based on the molecularly imprinted polymer (MIPs) particles as sensitive materials, tetracycline ion selective electrode and malachite green one were constructed. A series of ECL methods combined with molecularly imprinted polymer–solid phase extraction (MIP–SPE) were developed for quantitative determination of tetracyclines (TCs), malachite green (MG) and melamine (MA). The details are as follows:A highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using MIPs particles as quasi-ionophore. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1.0×10-8 mol/L. The electrode showed a linear Nernst response in the range of 2.0×10-8 to 1.0×10-3 mol/L with pH 2.0 4.0 and a slope of 59.8 mV/pC. Due to the specific recognition of tetracycline by the MIPs particles, the selectivity coefficients for routine interferences were less than 10-4. Finally, the proposed highly-sensitive ion selective electrode has been successfully applied to the determination of tetracycline in aqueous samples.PVC membrane malachite green selective electrode with high sensitivity was prepared with the ion-pair of malachite green–sodium tetraphenylborate as the electroactive substance, based on a two-dimensional functional material of restricted access media and molecularly imprinted polymers (RAM–MIPs), which could inhibit ion flux of MG, recognize MG specifically, and eliminate the matrix interference. The electrode showed a linear Nernst response in the range of 3.2×10-8 1.0×10-3 mol/L with pH 3.0 7.5 and a slope of 54.2 mV/pC. The low limit of detection was about 7.0× 10-9 mol/L. With the better selectivity, precision and accuracy, this electrode was practicable for the analysis of MG in aquatic water.An ECL inhibition method combined with MIP–SPE was developed for quantitative determination of four TCs in honey samples. MIPs were synthesized as solid phase extraction (SPE) sorbents, and MIP–SPE was used for the selective extraction and purification of TCs, and it was found that the four TCs strongly inhibited the ECL signal of Ru(bpy)32+/DBAE system. Based on the ECL signal changes, a simple and ultrasensitive detection method for TCs was thus established. Under the optimized conditions, the quenched ECL intensity versus the logarithm of the concentration of TCs is in good linear relationship over a concentration range from 4.0×10-11 to 4.0×10-9 g/mL. The method detection limits of TCs residues in honey samples were found to be 2.0×10-10 g/mL. The results obtained by the proposed ECL system, in terms of sensitivity, were much better than those of reported methods in literatures. In addition, the method was applied successfully to determine the total residuals of the four TCs in honey samples. A possible mechanism for the quenching effects of Ru(bpy)32+/DBAE system was also proposed.An ECL inhibition method combined with MIP–SPE was developed for quantitative determination of MG residues in fish. It was found that MG could strongly inhibit the ECL signal of luminol. Under the optimized conditions, the quenched ECL intensity versus the logarithm of the concentration of MG was in good linear relationship over a concentration range from 1.0×10-11 to 5.0×10-9 mol/L. The method detection limit of MG residues in fish was found to be 5 ppt. MIPs were synthesized as SPE sorbents, and MIP–SPE was used for the selective extraction and purification of MG. By carrying out the oxidation reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) which could convert leucomalachite green (LMG) into MG, this method was successfully applied to determine MG residues in fish. And, a possible mechanism for the quenching effects of MG on luminol was also proposed.An ECL enhancement method combined with MIP–SPE was developed for determination of melamine residues in dairy products. MIPs were synthesized as SPE sorbents, and MIP–SPE was used for the selective extraction and purification of MA, and it was found that melamine in a strong base solution is able to enhance the ECL of Ru(bpy)32+ at glass carbon electrode. Under optimized conditions, the enhanced ECL intensity was linearly proportional to the logarithm of melamine concentration in the range of 0.01 ppb 1.0 ppb, and the detection limit was 0.003 ppb. The method has been successfully demonstrated to determine melamine in dairy products including liquid milk, yogurt and milk powder samples. A possible mechanism for the ECL enhancement effect was also proposed.
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