1. Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, 33101 Tampere, Finland, RIKILT—Institute of Food Safety, Wageningen University and Research Centre, P.O. Box 230, 6700 AE Wageningen, The Netherlands, and BCC—Biosensing Competence Centre, P.O. Box 692, 33101 Tampere, Finland