| Chinese herbal medicine is an important part of the word of traditional medicine, which derived from China. O ur country already has more than ten thousand kinds of plants which have medicinal value up to now. It is the best compared with other countries and has a monopoly trend in the world. The use of Chinese herbal medicine has a history of nearly one thousand years. Due to its unique efficacy, great clinica l application value and research significance, the research and application of Chinese herbal medicine received widespread attention and recognition. The active ingredients of Chinese herbal medicine are the key elements of the Chinese herbal medicine. Now many new drugs from natural active ingredients of Chinese herbal medicine have been widely applied in clinic.Carbon element is one of the most close relationship with human elements existing in the nature. Carbon nanomaterials, such as Carbon Nanotubes（CNTs）, Graphene（Gr）, Graphene Oxidation（GO） and so on were widely researched by scientists because of their characters respectively. Many results showed that CNTs possess large specific surface area, good electron transfer properties, electrical catalytic properties and Gr has large specific surface area, good mechanical, thermal, electrical and optical properties. These properties make them widely used in many fields.Based on these, carbon nanomaterials（CNTs and GO） modified electrodes were used to investigate the electrochemical behavior of several active ingredients of Chinese herbal medicine systematically and simple and accurate method s of electrochemical analysis were established.The main research contents are divided into three parts below:1. In this part, a simple multi-walled Carbon nanotubes（MWCNTs） modified electrode（MWCNTs/GCE） was prepared by dropping. The electrochemical character of liquiritin was studied systermatically by a variety of electrochemical techniques. A possible electrochemistry reaction mechanism of liquiritin at the MWCNTs/GC E was proposed through the research of the effects of pH and scan rate. Under the optimum experimental conditions, electrochemical analysis method of liquiritin was established, and the linear ranges were 1.0×10-7 to 1.0×10-6 mol L-1 and 1.0×10-6 to 5.0×10-6 mol L-1 with the limit of detection 8.0×10-8 mol L-1.2. An electrochemical sensor, based on electrodeposition reduced graphene oxide modified glassy carbon electrode（ERGO/GCE）, was established and used for investigating the electrochemical behaviors of isofraxidin for the first time. A sensitive voltammetric method for determination of isofra xidin was proposed with wide detection linear range from 8.0×10-8 to 4.0×10-6 mol L-1 and low detection limit of 3.0×10-8 mol L-1. Simultaneously, some dynamics parameters of electrode process were calculated comprehensively and a possible reaction mechanism was proposed. Finally, the proposed method was successfully applied to detect isofraxidin in urine samples and Chinese herbal medicine Herba Sarcandrae with satisfactory results which provided a theoretical basis for the further pharmacological research.3. A highly sensitive voltammetric sensor, based on reduced graphene oxide on SWCNTs modified glassy carbon electrode（ERGO/SWCNTs/GCE）, was constructed and used for electrochemical behavior research and sensitive detection of the active ingredients of C hinese herbal medicine hesperetin. Based on the synergistic effect between ERGO and SWCNTs, the electrochemical response of hesperetin improved significantly at this sensor. So, a novel voltammetric method for determination of hesperetin was proposed. Under the optimum experimental conditions, the response currents were linear relationship with the hesperetin concentrations in the range of 5.0×10-8 to 3.0×10-6 mol L-1, with a detection limit of 2.0×10-8 mol L-1. The method was also applied successfully to detect hesperetin in urine samples and Chinese herbal medicine Flos buddlejae and results showed that the method has good selectivity and high sensitivity. |
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