Background:
The unnatural levels of dopamine (DA) result in serious neurological disorders
such as Parkinson’s disease. Electrochemical methods which have the obvious advantages of
simple operation and low-cost instrumentation were widely used for determination of DA. In order to
improve the measurement performance of the electrochemical sensor, molecular imprinting technique
and graphene have always been employed to increase the selectivity and sensitivity.
Methods:
An electrochemical sensor which has specific selectivity to (DA) was proposed based on the
combination of a molecular imprinting polymer (MIP) with a graphene (GR) modified gold electrode.
The performance and effect of MIP film were investigated by differential pulse voltammetry (DPV)
and cyclic voltammetry (CV) in the solution of 5.0 ×10-3 mol/L K3[Fe(CN)6] and K4[Fe(CN)6] with
0.2 mol/L KCl at room temperature.
Results:
This fabricated sensor has well repeatability and stability, and was used to determine the dopamine
of urine. Under the optimized experiment conditions, the current response of the imprinted
sensor was linear to the concentration of dopamine in the range of 1.0×10-7 ~ 1.0×10-5 mol/L, the linear
equation was I (µA) = 7.9824+2.7210lgc (mol/L) with the detection limit of 3.3×10-8 mol/L.
Conclusion:
In this work, a highly efficient sensor for determination of DA was prepared with good
sensitivity by GR and great selectivity of high special recognization ability by molecular imprinting
membrane. This proposed sensor was used to determine the dopamine in human urine successfully.
