| Ion chromatography (IC) is one of the fastest developing analytical methods due to its characteristics of speediness, convenience, good selectivity, high sensitivity. At presently, the analytical technique has been used in the fields of environmental, agricultural, industrial, food, clinical, biochemical and pharmaceutical analysis. In the 21st century, with the rapid progress of national economy, people are looking forward to having a higher living quality, the task of environmental monitoring, the causes of some pathologies and diagnosing, and therefore, become very important. IC analytical technique just caters to the need of these questions. In this dissertation, we put most our eyes on the development and application of ion chromatography combined with electrochemical detection and set up a series of analytical methods for the analysis of rain water, environmental water, urine, blood, plasma and red wine samples. The establishment of these analytical methods can provide a foundation for environmental monitoring, clinical diagnosing and food estimate. Our dissertation includes four parts and it may be summarized briefly as following:Part I PrefaceIn this part, ion chromatography was remarked generally. As an independent analytical method, IC has been used in many fields. The content of this paragraph includes six parts: general remarks of ion chromatography; types of ion chromatography; the common detection methods of ion chromatography; sample preparation; applications of ion chromatography and the innovations of this dissertation. In the remark part, the historical perspectives were supplied and advantages of ion chromatography wereintroduced. Subsequently, five separation models and five detection methods were elaborated. In the end, the sample preparation techniques and the applications of 1C in environmental, biochemical and beverage samples were summarized in detail.Part II Study on Ion Chromatography with Electrochemical Detection and Its Application in Environmental AnalysisThis part includes chapter 2 and 3. To select a sensitive detector in chromatographic analysis is an important step. In a general way, conductivity detector is applied extensively to analyze the common ions in ion chromatography. In this part, we set up two methods to determine some electroactive and electroinactive ions with amperometric detection in ion chromatography. In chapter 2, an amperometric detector based on the chemical modification of Nafion and Cobalt (II) hexacyanoferrate (IIJII) thin film (Nafion/Co-CN-Fe) onto a glassy carbon (GC) electrode was firstly developed for the determination of electroinactive cations (Li+, Na+, K+, Rb+, Cs+ and NH/) in single column ion chromatography. A set of well-defined peaks of electroinactive cation was obtained. The relative standard deviations (RSDs) of chromatographic peak height (nA) for these cations were all below 3.8%, the cations were detected conveniently in the linear concentration range of 6.0×10-6-5.0×10-3 mol L-1 and their correlation coefficients were all above 0.99. The detection limits of the cations were 9.2×10-6 mol L-1 for Li+, 3.4×10-6 mol L-1 for Na+, 6.3×10-7mol L-1 for K+, 7.8×10-7mol L-1 for Rb+, 6.2×10-7mol L-1 for Cs+ and 6.2×10-6mol L-1 for NH4+, at a signal-noise ratio of 3. The method wasquick, sensitive, simple and was successfully applied to the analysis of rainwater samples.Carbon nanotubes are novel nano-materials. They have been applied in many fields such as the tips in scanning probe microscopy, as field-effect transistors and as the storage of energy in supercapacitors due to their huge surface area, high electrical conductivity, good chemical stability and significant mechanical strength. In chapter 3, a glassy carbon electrode modified with multiwall carbon nanotubes (MWNT-COOHs) film was used as an amperometric sensor for the determination of S2O32-, SO32-, I" andSCN-. The electrochemical behaviors of these oxidizable inorganic anions at this modified electrode have been studied by cyclic voltammetry (C...
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