1. IMST—Department of Micro and Nano Systems Technology, HBV—Buskerud and Vestfold University College, Raveien 205, Borre 3184, Norway e-mail:
2. Department of Polymer and Composite Materials, SINTEF Materials and Chemistry, P.O. Box 124 Blindern, Oslo 0314, Norway e-mail:
3. The Intervention Centre, Oslo University Hospital (Oslo Universitetssykehus), Rikshospitalet, Postboks 4950 Nydalen, Oslo 0424, Norway e-mail: