Electrical impedance determination of cancer cell viability in a 3-Dimensional cell culture microfluidic chip

A technique of quantitative determination of cell viability in three-dimensional (3D) cell culture construct is proposed based on on-site electrical impedance measurement in a microfluidic chip. In vitro 3D cell culture has been interpreted for faithfully representation of the in vivo cellular responses in living tissues. However, monitoring of the cellular responses in 3D cell culture construct is normally time-consuming and labor-intensive. In this work, a microfluidicchip was developed and is capable of on-site determining cell viability in 3D construct without affecting the cellular behaviors. The chip mainly consisted of a culture chamber, in which a pair of vertical electrodes at its opposite sidewalls was embedded for measurement, and a fluidic channel for perfusion purpose. Cancer cells/agarose suspension was loadedinto the culture chamber for 3D cell culture with perfusing anti-cancer drug in different concentrations (6, 12, 18, and24 μg ml^-1) for 2 days. Since higher drug concentration led to more cell damage or death, the total impedance magnitude of the culture construct was shown to be reasonably proportional to the cell viability. The proposed technique has a high potential to develop a fast and easy measurement compared with the conventional cellular analysis techniques.