| In the last few years, nanotechnoly has attracted much attention and interest from researchers of various science fields. For the size of nanomaterials dependent optical, magnetic, electronic and catalytic properties due to their quasi zero space, nanomaterials have been heralded as the next generation of building block for designing new devices and technology. The utilization of such harmonized nanomaterials (HNM) will have a major impact on catalysis, sensor, optical, electronic, photo-electronic, piezoelectric ceramics and structural ceramic material applications.The research of nanomaterials in analytical electrochemistry has witnessed tremendous growth. The electrodes modified with some nanomaterials, such as carbon nanotubes, metal nano-particles and nano-composites have showed exciting characteristics: higher conducting ability, chemical stability and signal-to-background ratio (S/B). The application of nanomaterials in analytical electrochemistry is very helpful to set up new methods, new techniques and new theories in the relating fields. High performance liquid chromatography coupled with electrochemical detection (HPLC-ECD) has become one of the most important approaches in the fields of chemical, biological, medical and environmental analysis since its appearance in the 1970's for its high separation effectiveness, sensitivity and selectivity and its easiness of control. However, with the fast development of chemistry, biology, medicine, environment and other sciences, the conventional electrodes applied in electrochemical detection can't match with the requirements of the development. Therefore, it's essential to find new electrodes with higher sensitivity, lower detect limit and better stability to replace the conventional electrodes. Nanomaterials have exhibited outstanding advantages in application as electrode materials and they will be wildly used in HPLC-ECDIn this paper, Nanomaterials modified electrodes for HPLC-ECD are studied. Three parts of work have been performed in this thesis following an overall review.Part I: Platinum Particles Modified Electrode for Thiols DeterminationCoupled with HPLCAccording to the principle that Pt particles exhibit a better catalytic effect than smooth platinum in the oxidation of some organic substances, we prepared a novel chemically modified electrode (CME) by immobilization submicrometer-size Pt particles on normal Pt electrode in this work. The CME exhibited rather higher electro-catalytic capacity for L-cysteine (L-Cys), glutathione (GSH) and penicillamine (PEN) oxidation. Differential pulse amperometry was adopted for it can effectively improve the responses of these thiols by cleaning and reactivating the CME surface during the determination. The oxidation peak currents of L-Cys, GSH and PEN were linear to their concentrations in the scope of 2.5 X 10~7~1.0 X 10"4, 4.0 x10-7~1.0X 10-4 and 8.0 X 10-7~1.0X 104 mol L-1, with the calculated detection limits of 1.1X10'7, 1.8X10'7and 3.8X10'7mol I/1, respectively. The method has been successfully applied to assess the contents of L-Cys and GSH in rat striatal microdialysates.Part II: Simultaneous Determination of Aromatic Amines by HPLC Coupled with MWNT-COOH/Poly (3-methyIthiophene) Modified Dual-ElectrodeLiquid chromatography with amperometric detection (LC-AD) has been developed and applied to simultaneous determination of five kinds of aromatic amines in environmental water. Poly(3-methylthiophene) is an electronically conducting polymer which is found very stable toward oxygen, moisture and temperature in both doped and undoped states. On the other hand, carbon nanotubes have the ability to promote electron-transfer reactions when used as an electrode in chemical reactions. Therefore, in the LC-AD, a chemically modified electrode was fabricated based on MWNT-COOH coated with poly(3-methythiophene). It's found that this chemically modified electrode (CME) exhibited efficiently electrocatalytic ability for aromatic amines oxidation with relatively high sensitivity, stability and long...
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