A novel electrochemical sensor was proposed for the determination of dopamine (DA) based on the molecularly imprinted electropolymers (MIPs)/copper oxide (CuO) nanoparticles modified electrode. MIPs were firstly prepared by using nicotinamide as an environment-friendly monomer to selectively recognize the template molecules. CuO nanoparticles were used to enhance the number of imprinted sites per unit surface area of the electrode and then improve the selectivity and sensitivity of the electrochemical sensor. Thus, the obtained electrochemical sensor could effectively minimize the interferences caused by ascorbic acid (AA), uric acid (UA) and sample matrix. The linear range for the detection of DA was changed from 0.02 μmol L(-1) to 25 μmol L(-1) with the detection limit of 8 nmol L(-1) (S/N=3), which was lower than those of the reported MIPs-based sensor. Finally, the proposed method was applied to measure dopamine in serum samples. The spiked recoveries were changed from 96.9% to 105.9% and the RSD was not higher than 8.8%. It was shown that the proposed sensor exhibited significant promise as a reliable technique for the detection of DA in human serum samples.
Keywords: CuO nanoparticles; Dopamine; Electrochemical sensor; Electropolymerization; Molecularly imprinted polymers.
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