On-chip impedance magnitude of: (a) Drug susceptible 4T1 mouse breast cancer cells, (b) Drug tolerant 4T1 mouse breast cancer cells, (c) Drug susceptible B16-F10 mouse melanoma cells, and (d) Drug tolerant B16-F10 mouse melanoma cells. The impedance was measured at 0 h, 3 h, 5 h, 7 h, 9 h, and 12 h time points. Gel, Gel + Drug, Gel + Cancer Cell, and Gel + Cancer Cell + Media were used as controls. Error bars represent standard error of the mean.