Label and Immobilization Free Detection and Differentiation of Tumor Cells

This paper presents an electrical impedance spectroscopy based microfabricated sensor capable of detecting and differentiating tumor cells at single cell accuracy. Cell labeling, device functionalization, or cell capture were not required. Device consisted of a microfluidic channel etched in silicon with semi-parallel gold electrodes fabricated on channel side-walls. Device was tested with three human tumor cell lines and latex beads. All cell lines and latex beads were successfully detected. Differentiation between tumor cells from different cell lines was shown to be possible by analyzing channel impedance at two signal frequencies. Estimates for population opacity values were statistically calculated to be 1.119, 0.257, 0.664, and 0.332 for latex beads, MDA-MB-231 cells, MCF-7 cells, and SK-OV-3 cells, respectively. This device demonstrates a simple, mass-producible, and cost-effective approach for tumor cell detection in clinical and research procedures.