Quantitative impedimetric monitoring of cell migration under the stimulation of cytokine or anti-cancer drug in a microfluidic chip.

Cell migration is a cellular response and results in various biological processes such as cancer metastasis, that is, the primary cause of death for cancer patients. Quantitative investigation of the correlation between cell migration and extracellular stimulation is essential for developing effective therapeutic strategies for controlling invasive cancer cells. The conventional method to determine cell migration rate based on comparison of successive images may not be an objective approach. In this work, a microfluidic chip embedded with measurement electrodes has been developed to quantitatively monitor the cell migration activity based on the impedimetric measurement technique. A no-damage wound was constructed by microfluidic phenomenon and cell migration activity under the stimulation of cytokine and an anti-cancer drug, i.e., interleukin-6 and doxorubicin, were, respectively, investigated. Impedance measurement was concurrently performed during the cell migration process. The impedance change was directly correlated to the cell migration activity; therefore, the migration rate could be calculated. In addition, a good match was found between impedance measurement and conventional imaging analysis. But the impedimetric measurement technique provides an objective and quantitative measurement. Based on our technique, cell migration rates were calculated to be 8.5, 19.1, and 34.9 μm/h under the stimulation of cytokine at concentrations of 0 (control), 5, and 10 ng/ml. This technique has high potential to be developed into a powerful analytical platform for cancer research.