MICROWAVE DIELECTRIC SPECTROSCOPY OF LOW-VOLUME FRACTION HUMAN CANCER CELLS EMBEDDED IN COLLAGEN GELS - Experimental Feasibility Study with an Open-ended Coaxial Probe Topics: Biomedical Sensors; Electrical Bio-Impedance In Proceedings of the First International Conference on Biomedical Electronics and Devices - Volume 2: BIODEVICES, 156-161, 2008 , Funchal, Madeira, Portugal