1. Department of Chemistry and Materials Science, Aalto University, Kemistintie 1, 02150 Espoo, Finland
2. Department of Electrical Engineering and Automation, Aalto University, Tietotie 3, 02150 Espoo, Finland
3. Department of Pharmacology, University of Helsinki, Haartmaninkatu 8, 00290 Helsinki, Finland
4. Department of Clinical Pharmacology, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8C, 00290 Helsinki, Finland
5. Pain Clinic, Department of Anesthesiology, Intensive Care and Pain Medicine, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 2A, 00290 Helsinki, Finland
6. Department of Applied Physics, Aalto University School of Science, P.O. Box 15100, FI-00076 Aalto, Finland