石墨烯/壳聚糖电化学传感器对色氨酸对映体的选择性识别

Electrochemical Selective Recognition of Tryptophan Enantiomers Based on Graphene/Chitosan Composite Films

本文设计合成了一种石墨烯/壳聚糖复合物薄膜,并将其作为电化学电极应用于选择性检测具有旋光活性的色氨酸(Trp)对映体。采用X射线衍射、红外光谱、拉曼光谱、X射线光电子能谱、透射和扫描电子显微镜表征了石墨烯/壳聚糖复合物的结构。以石墨烯/壳聚糖复合物为电极,通过示差脉冲伏安法实现了Trp对映异构体的识别,结果表明L-Trp比D-Trp具有更高的电化学响应,并且峰电流密度和Trp的浓度在0.3×10-4~1.5×10-4 mol·L-1范围内有线性关系。该复合物电极具有厚度和面积可控、稳定性高等优点,可显著提高电化学检测中的电流信号,有望用于分子药物及临床医学领域中手性对映体的识别。

In this research,graphene/chitosan composite films were designed and used as electrode for electrochemical enantioselective recognition of tryptophan(Trp)enantiomers.The structure of the graphene/chitosan composite films were characterized using X-ray diffraction,FT-IR spectroscopy,Raman spectroscopy,XPS spectroscopy,transmission and scanning electron microscopy.Trp enantiomers were recognized using graphene/chitosan composite electrode by a differential pulse voltammetry.Experimental data indicated that L-Trp exhibited stronger electrochemical response than D-Trp,and that a linear relationship between the current density of the oxidative peak and the concentrations of L-/D-Trp was established in a concentration span ranging from 0.3×10-4 mol·L^-1 to 1.5×10-4 mol·L^-1.The composite electrode had a number of advantages including controllable thickness and area,good stability,and enhanced electrochemical signals.Therefore,the graphene/chitosan composite electrodes are expected to be used for enantioselective recognition in areas such as molecular drugs and clinical medicine.