Date of Graduation
A new strategy in devising two-terminal voltammetric sensors is described. In our approach, such detectors are obtained by using ionic forces to confine two different redox groups to the same surface. The one is analyte-sensitive, and acts as the sensing site, while the other is analyte-insensitive, and thus operates as the reference site. The layer-by-layer deposition technique enabled us to attach multilayer systems to the surface of a gold electrode. To these multilayers various redox couples can be bound by ionic forces. One combination of an iron-based pH-sensitive redox group in conjunction with ferri-ferrocyanide was used to demonstrate the working principle of the two-terminal voltammetric sensor, based on ionically assembled multilayer systems. Polyelectrolytes and redox couples were prepared for incorporation in multilayer assemblies. Multilayer systems with attached redox species were investigated by ellipsometry, cyclic voltammetry and AC impedance voltammetry. The electrochemical behavior of redox couples adsorbed to monolayer and multilayer systems was surveyed, and a two-terminal system was used for pH measurement. Quinone derivatives with an attached thiol group were synthesized for the use in voltammetric pH-detectors.
Lawy, Daniel Andrei, "Construction and characterization of monolayer and multilayer self-assembled systems with ionically bound redox centers." (1996). Graduate Theses, Dissertations, and Problem Reports. 9259.