| Studies on carbon nanotubes (CNT) become a hot topic in the world due to the unique one-dimensional tubular structure and subtle physical and chemical properties of CNT. Compared with other area, the application of CNT in analytical chemistry has been studied recently. In the present dissertation, using CNT as interfacial material, the functionalized CNT electrodes were constructed; the electrocatalysis and separation of CNT-modified electrodes and its recognition ability after incorporating cyclodextrins (CD) were studied firstly. This work may be of great signification for applying nano-material further. The main achievements obtained in this research include:1. CNT-coated electrode was constructed with CNT as electrode material for the electro-separation and simultaneous detection of neurotransmitters.The electrochemical characteristics of dopamine (DA) and epinephrine (EP) at multi-wall carbon nanotube coated graphite electrode have been investigated. The result demonstrated that the modified electrode shows enhanced sensitivity and excellent electrochemical discrimination to DA and EP, the cathodic potential difference of DA and EP was about 390 mV. DA and EP can be determined simultaneously in the presence of AA by their cathodic potential difference.2. CNT was functionalized successfully with supermolecular CD and further CD incorporating CNT modified electrodes (CD/CNT/CE) were constructed and characterizedCD solution has good dispersion behavior towards CNT. By SEM, TEM and FTIR characterization, we testified that CDs were adsorbed and attached to the surface of CNT due to hydrophobic interaction, van der Waals force and steric effect. It also shows the stereo-porous interface structure of electrode surface.CD can attach to the surface of CNT, which can enhance the solubility of CNT and be favorable to the properties of modified electrode. With the CD-CNT adduct, a novel interface architecture of electrode was constructed and it was characterized by a large aggregated pore of carbon nanotube captured CD with a small cavity. The perfect electrocatalytic properties of CNT coupled with the specific recognition properties of CD would indeed make for an ideal sensor.3. The voltammetric separation and recognition ability of CD/CNT/E for biomolecules and isomers were investigated systematically.(1). The electrochemical response of AA on CD/CNT/CE was investigated. The influence of different biocompatibility interfaces to electroactive analyte was discussed further. Modification of the electrode surface by carbon nanotubes reduced the overpotential for the redox process, and significantly increased the sensitivity of AA by incorporated a-CD. More importantly, the interference of DA can be avoided. Experiment results indicated that the oxidation treatment of CNT was unfavorable to the detection of AA.(2). a-CD/CNT/E exhibits perfect eletrocatalytic ability to CySH, which resolved the problem of electrochemical response reducing gradually due to oxidation products adsorption. The selective and sensitive determination of CySH was obtained.(3). Using neutral nitrophenol isomers as model compounds, the eletrocatalytic response and recognition ability of various cyclodextrins-incorporated carbon nanotube electrodes were firstly investigated and characterized systematically.(4). The electrochemical oxidation response of adenine and guanine on B-CD functionalized CNT modified electrode was described. The selective and sensitive determination of A and G was obtained and further estimate the contents of A and G in denaturing herring sperm DNA. Our work provides available approach to the amplified label-free electrochemical detection of DNA hybridization and the interaction with targeted agents.4. The electrocatalysis, separation and recognition mechanism of CNT modified electrode were investigated.The results suggest that the pronounced properties of CNT modified electrode come from its nano-dimension, subtle tubule structure and the spatial porous interfacial of aggregated...
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