氧化石墨烯/铁氰化铈修饰玻碳电极同时测定扑热息痛和咖啡因

采用滴涂法和电沉积法制备了氧化石墨烯/铁氰化铈(CeFe(CN)6)纳米复合膜修饰玻碳电极。用扫描电镜对氧化石墨烯和氧化石墨烯/CeFe(CN)6纳米复合膜进行了表征。分别用循环伏安法和差分脉冲伏安法研究了扑热息痛和咖啡因在修饰电极上的电化学行为。结果表明,在0.1 mol/L醋酸盐缓冲溶液(pH5.0)中,扑热息痛和咖啡因在此修饰电极上具有良好的电化学行为,扑热息痛和咖啡因分别在1.0×10-7～6.0×10-5mol/L和1.0×10-6～1.3×10-4mol/L浓度范围内与电化学响应信号呈良好的线性关系,相关系数分别为0.990和0.992;信噪比为3时,扑热息痛和咖啡因检出限分别为5.0×10-8mol/L和5.2×10-7mol/L。将本方法用于人尿样品分析,回收率为96.1%～105.4%。

Simultaneous Determination of Acetaminophen and Caffeine Based on Graphene Oxide/Cerium Hexacyanoferrate Modified Glassy Carbon Electrode

Graphene oxide was coated on glassy carbon electrode and cerium hexacyanoferrate was then electrodeposited on the modified electrode.Scanning electron microscope was used to characterize the modified electrode.The electrochemical behaviors of acetaminophen and caffeine on the modified electrode were investigated by cyclic voltammetry and differential pulse voltammetry.The experimental results showed that the electrochemical respond of acetaminophen and caffeine at the modified electrode was significantly improved in acetate buffer solutions(pH 5.0).The concentration of acetaminophen and caffeine showed good linear relationships with the oxidation peak current in the range of 1.0×10-7-6.0×10-5 mol/L and 1.0×10-6-1.3×10-4 mol/L,with correlation coefficients of R=0.990 and 0.992,respectively.The limits of detection for acetaminophen and caffeine were 5.0×10-8 mol/L and 5.2×10-7 mol/L(S/N= 3),respectively.The developed method was used to the determination of spiked urine samples with recoveries of 96.1%-105.4%.