Abstract
The objective of this work is the study of the transport through lipid membranes of water and ions using self-assembled artificial channel structures and the design of nano sized self-assembled organic contacts for macroscale applications: biocathodes.The first part focuses on the transport through membrane bilayers. The objective is to replicate the function of naturally occurring proteins using ureido-hetreocycle compounds. The influence of species composition is assessed versus the supramolecular structure it generates and the link between it and activity. The first chapter treats the transport of ions through the lipid bilayers of large unilamellar vesicles (LUVs), in terms of total activity and selectivity vs. the structure of compounds. The second chapter refers to the transport of water on LUV systems. Here, a combined approach was used in evaluating the channels' activity, by placing them both on the outside of the liposomes but also directly in the lipid layer. Finally the protons transport of these structures was assessed reveling very efficient proton channels. The third chapter has an interdisciplinary approach combining several topics. The triaryl amines (TAAs) have to propriety of forming self-assembled nano sized fibrils when irradiated by the generation of cation-radicals. These present a directional electronic conduction pathway and are reported to display metal-like conductivity. These fibrils, which unravel in the absence of light, provide interesting possibilities as organic nano scale electrical contacts. A matrix of mesoporous silica was created via electrodeposition in order to enclose the TAAs in a confined medium. The novelty of the approach is that the system only has electron conductivity trough the TAAs nano wires while the silica mass is insulating. The resulting device's proprieties were characterized and further it was used as a bio cathode. The biocathodes containing the enzyme Laccase were then tested to prove the functioning of the matrix of nano contacts as the only providers of electrons to the enzyme.