A simple and sensitive cytosensor based electrical characterization of in vitro wound healing assay for keratinocytes

Confluent monolayers of cells in culture media are usually fragile and are susceptible to mechanical disruption. To assess the growth and migration of the cells towards recovery, the mechanical disruption is often done deliberately to perform wound healing assay. In such analysis, after a scratch in the cell monolayer, electrical characterization has been done to provide related quantitative description of the cellular behavior compared to the microscopic observation. In this direction for cellular electrical characterization, biosensors are usually designed with photolithographically patterned electrodes which are of the dimensions of the cells. This increases the cost and complexity of the analysis. Here we report the electrical characterization of in vitro wound healing for keratinocytes monolayer in DMEM-F12 medium with a low cost and sensitive macroporous silicon platform using simple electrode geometries for the first time. Impedance spectroscopy results show that there is a distinct difference between the electrical properties like the effective capacitance and the resistance of the keratinocytes (HaCaT) in the frequency range from 100Hz to 1MHz at two different time instants after wounding. The difference in the electrical properties has been qualitatively explained with the microscopic and immunocytochemical findings. This analysis may help to assess the cell behaviour during its growth and repair through a less complex and low cost electrical route.