Azalia Riklin

Application of stilbene-(4,4′-diisothiocyanate)-2,2′- disulfonic acid as a bifunctional reagent for the organization of organic materials and proteins onto electrode surfaces

Abstract Trans -stilbene-(4,4′-diisothiocyanate)-2,2′-disulfonic acid (DIDS) acts as a bifunctional reagent for the organization of redox functionalized monolayers. Treatment of gold electrodes by cystamine generates the respective thiol-monolayer-modified gold electrode with a surface density corresponding to 5.4 × 10 −11 Mol cm −2 . Treatment of the cystamine-modified gold electrode with DIDS generates an active monolayer that can be further coupled to redox functionalities such as the amino quinone. The resulting quinone-monolayer-modified electrode displays electrochemical activity. Similarly, the cystamine + DIDS-monolayer-modified electrode reacts with amino functionalities of redox proteins, i.e. glutathione reductase. The resulting enzyme monolayer-gold electrode assembly is wired towards electron-transfer communication by covalent attachment of N -methyl- N ′-(6-hexanoic acid)-4,4′-bipyridinium iodide as the electron relay component.

Photoinduced carbon dioxide fixation forming malic and isocitric acid

Photoinduced CO2-fixation into organic substrates is accomplished via enzyme-catalysed reactions.

Interacting Light Energy with Biocatalytic Assemblies: Biocatalysed Photosynthesis and Photoregulation of Enzymes

Light energy can be coupled to biocatalytic assemblies by two basic features. First, solar light could provide the energy input for biocatalysed syntheses, similar to the performance of the photosynthetic cycle in nature. Thereby, light-induced biocatalysed processes mimicking photosynthesis could provide a novel biotechnological approach. Second, interaction of light energy with enzymes could eventually trigger their activities “on” or “off”. As a result, enzymes could be photoregulated by external light signals and the application of biocatalytic materials as biochemical switches in sensor devices or information storage systems seems feasible. This article will describe the progress of our laboratory in harnessing light energy in the performance of biocatalytic assemblies.