A Highly Sensitive and Stable Electrochemical Sensor for Simultaneous Detection of Dopamine and Uric Acid Based on the Phosphovanadotungstate and CNTs Decorated By Chitosan

Abstract

In current work, a highly sensitive and stable electrochemical sensor for simultaneous detection of dopamine (DA) and uric acid (UA) is constructed based on the phosphovanadotungstate (P2W17V), and CNTs decorated by chitosan (CNTs-CS). The combination of two active components endows the electrode with large specific surface area, high electrical conductivity and excellent electrochemical activity. The proposed sensor displayed excellent electrocatalytic performance towards DA and UA by differential pulse voltammetry in 0.2 M phosphate buffer solution (pH = 7.0). For the mixture containing DA and UA, the two compounds can well separate from each other with a potential difference of 101 mV. The sensor exhibited a linear dependence on DA and UA concentration ranging from 2.25×10-6 to 2.81×10-4 M and 1.25×10-6 to 1.66×10-4 M with a detection limit of 0.35 and 0.65 μM (S/N = 3), respectively. The influence of several possible co-existing substances were investigated. The applicability of the method for real samples analysis was tested by determination of DA and UA in bovine serums. This new sensor holds great promise for sensitive determination of DA and UA in real application. (This paper is funded by the International Exchange Program of Harbin Engineering University for Innovation-oriented Talents Cultivation.) Figure 1