Characterization and Bioelectrocatalytic Peoperties of Cytochrome c and Hemoglobin by Direct Electrochemistry of DNA and Nafion and Poly (FeTAPP) Incorporated with Multi-walled Carbon Nanotubes Modified Electrodes
| Autor: | Jan-Wei Shie, 謝臻蔚 |
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| Rok vydání: | 2006 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 95 Part Ⅰ：A novel conductive biocomposite film (MWCNTs-DNA-cyt c) containing multi-walled carbon nanotubes (MWCNTs) incorporated with DNA and cytochrome c (cyt c) was synthesized on glassy carbon electrode (GCE), gold (Au) and indium tin oxide (ITO) by potentiostatic methods. The presence of both MWCNTs and DNA in the biocomposite film enhanced the surface coverage concentration (Γ), increased the electron transfer rate constant (Ks) to 21 % and decreased the degradation of cyt c. The biocomposite film also exhibited a promising enhanced electrocatalytic activity towards the reduction of halogen oxyanions and oxidation of biochemical compounds such as ascorbic acid and L-cysteine The biocomposite films were also produced on Au electrode using electrochemical quartz crystal microbalance（EQCM） studies, which revealed the enhancements in the functional properties of MWCNTs, DNA and cyt c. The surface morphology of the biocomposite films deposited on transparent semiconductor ITO were studied using scanning electron microscopy, which revealed that DNA and cyt c were incorporated on MWCNTs. PartⅡ：A conductive composite film (MWCNTs-NF-Hb) containing MWCNTs incorporated with nafion (NF) and hemoglobin (Hb) was synthesized on GCE, Au, ITO and screen printed carbon electrode (SPCE) by potentiostatic methods. The presence of both MWCNTs and NF in the composite film enhanced the Γ increased the Ks to 132 %. The composite film also exhibited promising enhanced electrocatalytic activity towards the reduction of O2, H2O2 and CCl3COOH. The MWCNTs-NF-Hb modified GCE sensitivity values were higher than the values obtained for other film modified GCEs. The composite films were also produced on Au electrode using EQCM studies, which revealed the enhancements in the functional properties of MWCNTs, NF and Hb. The surface morphology of the composite films deposited on transparent semiconductor ITO were studied using scanning electron microscopy, which revealed that NF and Hb were incorporated on MWCNTs. the flow injection analysis was used for the amperometric studies of analytes at MWCNTs-NF-Hb film modified SPCE. Part Ⅲ：A novel conductive composite film (MWCNTs-PFeTAPP) containing multi-walled carbon nanotubes (MWCNT) with poly(iron tetra(o-aminophenyl) porphyrin) (PFeTAPP) was synthesized on glassy carbon electrode (GCE), gold (Au) and indium tin oxide (ITO) by potentiostatic methods. The presence of MWCNTs in the composite film enhanced the surface coverage concentration (Γ) of PFeTAPP. The composite film exhibited a promising higher catalytic activity towards the reduction of compounds such as oxygen (mediated by myoglobin) and hydrogen peroxide in pH＝1.5 aqueous solution. The cyclic voltammetry (CV) was used for the measurement of electroanalytical properties of the analytes by means of composite film modified electrodes. Further the composite films produced on Au electrode were used for EQCM studies, which revealed the enhancements in the functional properties of MWCNTs and PFeTAPP. The surface morphology of the composite films deposited on transparent semiconductor ITO were studied using scanning electron microscopy and atomic force microscopy, which revealed that PFeTAPP incorporated on MWCNTs. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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