Chemical induced impedance spectroscopy for single cancer cell detection

This paper reports a MEMS-based impedance spectrometer capable of detecting a single MDA-MB-231 human breast cancer cell in a background of normal MCF10A breast epithelial cells. This has been achieved by 1) stimulating a selective increase in the cancer cell area using the FDA-approved anti-cancer drug SAHA which resulted in a cancer-specific rise in bioimpedance and 2) utilizing a unique thin multi-branched electrode configuration that induced linear cell alignment along the electrode resulting in increased sensitivity. A 5% rise in bioimpedance in response to only 550nM of SAHA was a reliable biomarker for the presence of one or more cancer cells on the electrode. The bioimpedance response to SAHA was rapid and detectable as early as 30min.