Fabrication of self-assembled monolayer of 8-mercaptoquinoline on polycrystalline gold electrode and its selective catalysis for the reduction of metal ions and the oxidation of biomolecules

It was found out that 8-mercaptoquinoline (MQ) could form very compact and even self-assembled monolayer (SAM) on polycrystalline gold electrode surface, which can exist for several days without changing its electrochemical properties. The SAMs of 8-mercaptoquinoline selectively catalyzed the reduction of Ga3+, In3+ and Cr6+ while blocked the electrochemical reaction of other metal ions on the electrode surface. It was also found out that the SAMs of 8-mercaptoquinoline selectively catalyzed the oxidation of NADH, uric acid and ascorbic acid. (C) 2003 Published by Elsevier B.V.