1. Physics of Fluids Group, MESA+ Institute for Nanotechnology, Technical Medical (TechMed) Center, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
2. Bracco Suisse S.A., Route de la Galaise 31, 1228 Plan-les-Ouates, Switzerland
3. Tide Microfluidics B.V., Capitool 41, 7521 PL Enschede, The Netherlands