Impedance analysis of single melanoma cells in microfluidic devices

The electrical impedance analysis of single cells can provide information on cells' pathological condition in various environments. Cell electrical properties are affected by factors such as the location, adhesion, and size of the cell. The proposed microfluidic device captures a single cell, maintains growth conditions, and allows single-melanoma-cell impedance to be measured using an impedance analyzer and a function generator. The rate of impedance variation (ROIV) can be used to determine cell growth conditions. Cellular apoptosis affects cell size and membrane surface area, and thus the electrical properties of cells. At 24 h without Antrodia cinnamomea (AC) addition, ROIV was 15.23%, 17.04%, and 12.60% at temperatures of 34 °C, 37 °C, and 40 °C, respectively. At 24 h and 378C, ROIV was 17.04%, 40.37%, and 45.02% for AC concentrations of 0, 20, and 40 μL/mL, respectively. The results show that the cell impedance variation of cells cultured without AC is much lower than that of cells cultured with AC. Regarding cellular morphology, with AC addition, the cells shrank obviously after 24 h, whereas they barely shrank without AC addition.