线状纳米金修饰碳纤维超微电极检测芦荟大黄素

该文建立了芦荟大黄素(AE)的电化学检测方法。通过柠檬酸三钠还原氯金酸制备线状纳米金,采用一步恒电位沉积方法将线状纳米金沉积在碳纤维超微电极(CFME)表面,考察了电极修饰前后对AE的电催化性能,得到最佳修饰时间为12 min。结果表明,线状纳米金修饰碳纤维电极(LGN/CFME)的氧化峰电流与AE浓度在2.0×10-6~1.0×10-4 mol/L范围内呈良好线性关系,线性方程为Ip(nA)=0.318 1C(μmol/L)+25.01,r2=0.965 3,检出限(S/N=3)为6.19×10-7 mol/L,说明此方法可用于芦荟汁中AE的定量检测。

Determination of Aloe Emodin by Carbon Fiber Ultramicroelectrodes with Linear Gold Nanoparticles

An electrochemical method with linear gold nanoparticles modified carbon fiber ultramicroelectrodes(LGN/CFME) was proposed for the detection of aloe emodin(AE).The LGN/CFME were prepared with chloroauric acid reduced with sodium citrate,depositing on the surface of CFME by one-step potentiostatic deposition.The electrocatalytic performance of the CFME towards AE before and after electrode modification was investigated,and the optimal deposition time was 12 min.Results showed that there was a good linear relationship between oxidation peak current and AE concentration in the range of 2.0×10-6-1.0×10-4 mol/L,with a correlation coefficient(r2) of 0.965 3 and a linear regression equation of Ip(nA)=0.318 1 C(μmol/L)+25.01.The detection limit(S/N=3) was 6.19×10-7 mol/L.The method could be applied in the determination of AE in aloe juice.