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

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 X 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.