| Chemically modified electrode was developed since 1970s, and had been widely applied in the fields related to environmental science, life science, materials science, energy power, electronics, etc. With the advancement in the study of chemically modified electrodes, the composite electrodes whose performance were higher than that of conventional metal electrodes can been manufactured through combination of some kinds of modifiers of good chemical properties with metal electrodes. Though there were many types of chemically modified materials, Prussian blue was one of the most widely used, such as in the fields of functional materials, electrochemical sensors, ion identification and molecular magnetic materials, etc, due to its advantages of unique structure, good chemical and electrochemical stability, low cost. By means of doping Eu3+ ions in the Prussian blue, a film called europium-doped Prussian blue analogue (Eu-PB) film whose performance was superior to that of the Prussian blue was prepared. With combination of the advantages of both the europium-doped Prussian blue (Eu-PB) film modified electrode and the coventional bismuth film electrod, an europium-doped Prussian blue (Eu-PB) composite bismuth film was prepared using the electrochemical deposition method, and the samples analysis was made on this electrode. The results of the experiments showed that the europium-doped Prussian blue (Eu-PB) composite bismuth film can been successfully used in the determination of trace Indium in environmental water samples, the determination of trace Zinc in dairy products and the determination of isoniazid in pharmaceuticals. This electrode had the advantages of high sensitivity, good stability, wide potential window, high anti-interference performance, long service life. Therefore, this electrode had high potential value for application.This thesis includes the following four chapters:Chapter I: OverviewThis chapter described the characteristics of potential stripping analysis, the role of mercury membrane in electrochemical stripping analysis, and the characteristic of mercury film. Then it introduced the features of bismuth and its compounds, the preparation methods and applications of the bismuth film electrode. It also briefly discussed the necessity, preparation and application of the chemically modified bismuth film composite electrode. The last part of this chapter prespectd the development trends of the europium-doped Prussian blue (Eu-PB) composite bismuth film electrode in potential stripping analysis, and included the purpose and significance of the research in this thesis. The references of this part included a total of 104 items.ChapterⅡDetermination of Trace Indium in Water Samples by Anodic Stripping Voltammetry on Composite Bismuth Film ElectrodeA novel composite bismuth film electrode (GC/Eu-PB/BFE) was prepared by electrodepositing bismuth film on the glassy carbon matrix which was modified with europium-doped Prussian blue analogue (Eu-PB). In addition, trace levels of Indium was determined by anodic stripping voltammetry using the GC/Eu-PB/BFE as a working electrode. The comparison of stripping properties of In3+ between the common bismuth and the composite bismuth had been studied. Some of effect factors such as the thickness of bismuth film, supporting electrolyte, pH of determining solution, deposition time and deposition potential were optimized. Under the optimum conditions, good linearity was obtained in the concentration range of 220μg/L and 20100μg/L, respectively. The limit of detection was 0.15μg/L and relative standards error was under 2.0%. The method had been applied to the determination of Indium ion in environment water samples with the recovery of 97.5%103%。The results showed that the composite bismuth film (GC/Eu-PB/BFE) had been applicable to analysis with high sensibility and good stability.ChapterⅢDetermination of Trace Zinc by Anodic Stripping Voltammetry Composite Bismuth Film ElectrodeA composite bismuth film electrode (GC/Eu-PB/BFE) was prepared by electrodepositing bismuth film on the glassy carbon which was modified with europium-doped Prussian blue (Eu-PB). A new method for the determination of zinc was developed using the GC/Eu-PB/BFE. The results revealed that the sensitive stripping peak of zinc ions was obtained in 0.03 mol/L tartrate solutions (pH=4.5). Under the optimum conditions, the good linearity of zinc ions were obtained in the concentration range of 10540μg/L (r=0.99987) after 120 s'deposition at -1.4 V. The limit of detection was 1.38μg/L (S/N=3) and relative standards error was 0.94% (n=8). The method had been applied to the determination of zinc in dairy and medicine samples with the recovery of 99.3%101.2%.ChapterⅣDetermination of isoniazid in medicine by Anodic Stripping Voltammetry on Composite Bismuth Film ElectrodeThis paper presented an analytical method which was used in determination isoniazid in drug by composite bismuth film electrode anodic stripping voltammetry. The method was used to determine isoniazid in 0.01 M acetic acid-sodium acetate buffer solution. The composite bismuth film electrode was used as the working electrode, the saturated calomel electrode was used as a reference electrode and platinum electrode was used as an auxiliary electrode. The good linearity between peak current and concentration was obtained in the concentration range of 8.0×10-82.0×10-6 mol/L. The limit of detection was 1.8×10-8 mol/L after 60 s deposition procedure. It can be seen from obtained results that the composite bismuth film working electrode had advantages of high linear range, good reproducibility and performance. Moreover, satisfied results of measuring isoniazid were got.
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