Electric Cell-Substrate Impedance Sensing (ECIS) for Analyzing the Effect of Environmental Pollutants - A Study of Diesel Exhaust Nanoparticles

the Effect of - A Abstract ECIS is a morphological biosensor that records the electrical properties of cell-covered microelectrodes in an AC circuit, including impedance (ohm), resistance (ohm), and capacitance (μFarad). The objective of the current study was to analyze the suitability of ECIS as a label-free in vitro assay system to understand the effect of external stimuli on cells in real-time, vis-à-vis regular endpoint assays of cytotoxicity. The study analyzed whether fluctuations in the electrical properties of cell-covered microelectrodes reflected dynamic changes in cell morphology on exposure to diesel exhaust particles. Exposure of A549 monolayers in 8 well microarrays to DEP caused significant changes in microelectrode resistance (ohm @4 kHz) like MTT, LDH, and NRU assays and observed corroborative endpoint results. Reactive oxygen species production by DCFHDA assay showed an increase in relative fluorescence indicating ROS to be a possible cause of dose-dependent cytotoxicity. Our findings indicate that ECIS provides many benefits as an alternative method to quantify, automate, and measure the effect of pollutants or particles in real-time when compared to traditional endpoint methods.