采用滴涂法制备三维石墨烯/L-胱氨酸复合物修饰电极(3DGR/L-CysS/GCE),并用电化学交流阻抗谱(EIS)和扫描电镜(SEM)对电极材料进行表征.以循环伏安法(CV)、恒电位库伦分析法(CPC)、差分脉冲伏安法(DPV)和计时电量法(CC)研究了氯氮平在该修饰电极上的电化学行为.实验结果表明:在pH6.8的 Na2HPO4-NaH2PO4溶液中,氯氮平在3DGR/L-CysS/GCE上是单电子和单质子转移的电化学反应,在2.0×10-5~5.0×10-4 mol/L浓度内,氧化峰电流与氯氮平的线性关系良好,其检出限(S/N=3)为1.21×10-6 mol/L.样品测定的回收率为97.5%~100.8%.
The 3DGR/L-CysS/GCE was prepared by drop-coating method, and characterized by electrochemical impedance spectroscopy(EIS)and scanning electron microscopy(SEM). The electrochemical behaviors of clozapine at 3DGR/L-CysS/GCE were studied by cyclic voltammetry(CV), controlled potential coulometry(CPC), differential pulse voltammetry(DPV)and chronocoulometry(CC). The experimental results showed that the reaction of clozapine at 3DGR/L-CysS/GCE was an electrochemical reaction with one electron and one proton transfer. The peak current and clozapine content showed a good linear relationship in the concentration range of 2.0×10-5~5.0×10-4 mol/L, and the detection limit was 1.21×10-6 mol/L(S/N=3). 3DGR/L-CysS/GCE was used for the determination of clozapine in tablets, and the recovery was 97.5%~100.8%.
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