Lian Qianwen, He Zhifang, He Qian, Luo Ai, Yan Kaiwang, Zhang Dongxia, Lu Xiaoquan, Zhou Xibin
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Geography and Environment Science, Northwest Normal University, Lanzhou, 730070, PR China.
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, 730070, PR China.
Anal Chim Acta. 2014 May 1;823:32-9. doi: 10.1016/j.aca.2014.03.032. Epub 2014 Mar 25.
A new type of tryptophan-functionalized graphene nanocomposite (Trp-GR) was synthesized by utilizing a facile ultrasonic method via π-π conjugate action between graphene (GR) and tryptophan (Trp) molecule. The material as prepared had well dispersivity in water and better conductivity than pure GR. The surface morphology of Trp-GR was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA), and uric acid (UA) were investigated by cyclic voltammetry (CV) on the surface of Trp-GR. The separation of the oxidation peak potentials for AA-DA, DA-UA and UA-AA was about 182 mV, 125 mV and 307 mV, which allowed simultaneously determining AA, DA, and UA. Differential pulse voltammetery (DPV) was used for the determination of AA, DA, and UA in their mixture. Under optimum conditions, the linear response ranges for the determination of AA, DA, and UA were 0.2-12.9 mM, 0.5-110 μM, and 10-1000 μM, with the detection limits (S/N=3) of 10.09 μM, 0.29 μM and 1.24 μM, respectively. Furthermore, the modified electrode was investigated for real sample analysis.
通过石墨烯（GR）与色氨酸（Trp）分子之间的π-π共轭作用，利用简便的超声方法合成了一种新型的色氨酸功能化石墨烯纳米复合材料（Trp-GR）。所制备的材料在水中具有良好的分散性，并且比纯GR具有更好的导电性。通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）和拉曼光谱对Trp-GR的表面形态进行了表征。采用循环伏安法（CV）研究了Trp-GR表面抗坏血酸（AA）、多巴胺（DA）和尿酸（UA）的电化学行为。AA-DA、DA-UA和UA-AA的氧化峰电位分离约为182 mV、125 mV和307 mV，这使得能够同时测定AA、DA和UA。采用差分脉冲伏安法（DPV）测定混合物中的AA、DA和UA。在最佳条件下，测定AA、DA和UA的线性响应范围分别为0.2-12.9 mM、0.5-110 μM和10-1000 μM，检测限（S/N=3）分别为10.09 μM、0.29 μM和1.24 μM。此外，还对修饰电极进行了实际样品分析研究。
