目的:制备出磷钨酸铈纳米晶负载的碳纳米管修饰电极,研究多巴酚丁胺(DBTM)在该修饰电极上的电化学行为,建立DBTM含量测定的示差脉冲伏安新方法。方法:用浸渍法制备负载磷钨酸铈(CePW)复合材料的CePW/LDWNT修饰电极,用电化学阻抗(EIS)对修饰电极进行表征并考察多巴酚丁胺在不同电极体系中的循环伏安特性。结果:制备的纳米复合物对DBTM具有催化氧化作用,DBTM的氧化峰电流与浓度在2.0×10-6~8.0×10-6mol·L-1范围内呈线性关系,线性回归方程为ip=-10.06+5.824C,r=0.9966,检测限为5.8×10-9mol·L-1(S/N=3)。结论:该法灵敏度高,选择性及重现性好,可用于盐酸多巴酚丁胺注射液中多巴酚丁胺的测定。
Objective:To prepare cerium tungstophosphoric acid(CePW) nanoparticles/double-walled carbon nanotubes nanocomposite and investigate the electrochemical behavior of dobutamine(DBTM) on the modified electrode,so as to establish a differential pulse voltammetry method for DBTM determination.Method:Electrochemical impedance spectroscopy(EIS) was used to characterize the modified electrode and study cyclic voltammograms of DBTM at different electrodes.Results:The nanocomposite modified electrode exhibited strong promoting effect and high stability toward the electrochemical oxidation of dobutamine.Under optimal conditions,a good linear relationship(i.e.,ip=-10.06 +5.824C) was obtained between anodic peak current and dobutamine concentration in the range of 2.0×10-6-8.0×10-6 mol·L-1 with a detection limit of 5.8-10-9 mol·L-1(S/N=3) by differential pulse voltammetry.Conclusion:The method showed excellent sensitivity,good selectivity and reproducibility,and can be used for the determination of DBTM in Dobutamine Hydrochloride injection.