柠檬酸修饰玻碳电极检测卡比多巴含量研究OA

Four kinds of glassy carbon electrode are prepared to determine carbidopa(CD),which are modified with citric acid,p-phenylenediamine,p-aminobenzene sulfonic acid or L-glutamine by constant potential deposition method.The experiment results show that the glassy carbon electrode modified with citric acid(CA/GCE)exhibits a better selectivity and high sensitivity compared with other electrodes,when it's used to determine the CD.The electron transfer ability of the modified electrode is characterized by using the cyclic voltammetry and electrochemical impedance spectra.The detection ability of CA/GCE electrode for CD in CD-LD compound tablets is investigated by differential pulse voltammetry(DPV).The oxidation peak current at 0.65 V in the phosphate buffer solutions(pH=5.8)is linearly dependent on the CD concentrations in the range of 4.0×10-6～1.0×10-4 mol/L.The proposed electrode shows potential applications in the detection of CD in CD-LD compound tablets,and the relative error is within±5%.