基于十二烷基磺酸钠功能化石墨烯负载SnO_2纳米粒子复合修饰电极制备L-色氨酸电化学传感器

Preparation of L-tryptophan Electrochemical Sensor Based on Sodium Dodecyl Sulfate Functionalized Graphene Supported SnO_2 Nanoparticles Composite Modified Electrode

研制了一种新型的电化学传感器——十二烷基磺酸钠功能化石墨烯(SDS-GN)负载SnO_2纳米粒子(SnO_2NPs)复合修饰碳糊电极(SDS-GN@SnO_2NPs/CPE)。采用循环伏安法(CV)和线性扫描伏安法(LSV)探讨了L-色氨酸(L-Trp)在该电极上的电化学行为。结果表明:在最佳条件下,L-Trp的氧化峰电流与其浓度在5.0×10^(-7)～3.0×10^(-5) mol/L和3.0×10^(-5)～5.0×10^(-4) mol/L范围内均有良好线性关系,检测限(S/N=3)为3×10^(-7) mol/L。将此法用于实际样品(氨基酸口服液)中色氨酸的测定,加标回收率为97.3%～104%。

A novel electorchemical sensor(SDS-GN@SnO2NPs/CPE)based on sodium dodecyl sulfate functionalized graphene supported SnO2 nanoparticles composite modified carbon paste electrode has been developed.The electrochemical behavior of L-Trp on the electrode was investigated by cyclic voltammetry(CV)and linear scanning voltammetry(LSV).That result shows that under the optimum conditions,the oxidation peak current of L-Trp has a good linear relationship with its concentration in the range of 5.0×10^-7~3.0×10^-5 mol/L and 3×10^-5~5.0×10^-4 mol/L,the correlation coefficients are R=0.998 0and R=0.998 9,and the detection limit(S/N=3)is 3×10^-7 mol/L.The method was applied to the determination of tryptophan in the actual sample(amino acid oral liquid),and the recovery rate was 97.3%~104%.