Simultaneous Electrochemical Detection of Uric Acid and Dopamine Based on Graphene Quantum Dot Modified Glassy Carbon Electrode / 现代检验医学杂志

ABSTRACT

Objective To preparegraphene quantum dots (GQDs) and construct a novel biosensor for determination of dopamine (DA) and uric acid (UA).Methods The GQDs was prepared by carbonization method from citric acid as carbon sources.Differential pulse voltammetry was used by the modified electrodes to detect uric acid and dopamine,and the detection performance was evaluate.Collected three experimenters morning urine on July 29,2016.The proposed sensor was used for biological samples detection.Results The size of GQDs were between 3 to 5 nm,which was observed by transmission electron microscopy (TEM).The proposed sensor had good linear correlation of 50～600 μmol/L UA (r2 =0.996 6) and 2～ 240 μmol/L DA (r2 =0.992 5).In uric acid in urine samples' detection (n=3),RSD value was less than 3％.The standard addition recovery rates of UA and DA were in 95.7％～101.4％ and 96％～102％ respectively.Conclusion The biosensor based on GQDs for determination DA and UA had been constructed successfully.