1. Analytical Chemistry – Center for Electrochemical Sciences (CES) Faculty of Chemistry and Biochemistry Ruhr University Bochum Universitätsstraße 150 D-44801 Bochum Germany
2. Present address: PPG (Deutschland) Business Support GmbH PPG Packaging Coatings Erlenbrunnenstraße 20 D-72411 Bodelshausen Germany
3. Instituto de Tecnologia Química e Biológica António Xavier Universidade Nova de Lisboa Av. da República 2780-157 Oeiras Portugal