1. School of Materials Science and Engineering and Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, Singapore 637553, Singapore
2. Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Göteborg, Sweden
3. School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore