A detailed, unified description of electrocatalytic mechanisms at organic conducting salt (OCS) electrodes, tetrathiafulvalene tetracyanoquinodimethane (TTFTCNQ) and hexamethylenetetratellurafulvalene tetracyanoquinodimethane (HMTTeFTCNQ), has been presented. A wide spectrum of behavior is observed depending on the electrochemical and kinetic characteristics of the analyte of interest, the nature of the OCS, and the applied potential. Both direct electron transfer and indirect (homogeneous and heterogeneous) mediation mechanisms are shown to arise, depending on the experimental conditions. / The redox chemistry of the coenzyme, pyrroloquinoline quinone (PQQ), has been investigated in detail as a function of metal complex formation and pH. The characterization of PQQ and its metal complexes provides insight into the redox chemistry of the 15-lipoxygenase active site. / A biosensor involving the coupling of a PQQ-enzyme, methanol dehydrogenase (EC 1.1.99.8.), to a TTFTCNQ electrode has been developed. Characterization of this enzyme membrane electrode shows that the substrate-reduced enzyme is rapidly turned over at the TTFTCNQ electrode whereas no turnover is evident at a conventional electrode. Enzyme properties (K$ sb{ rm me},$ stability, T$ sb{ rm sensitivity},$ pH dependence, substrate selectivity), when interfaced to the electrode, are reported.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.70278 |
| Date | January 1992 |
| Creators | Zhao, Shishan |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001288659, proquestno: AAINN74595, Theses scanned by UMI/ProQuest. |
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