Eukaryotic cell lines as a sensitive layer for direct monitoring of carbon monoxide

In the past years, whole cell gas toxicity assays have been developed in order to study the harmful effects of gaseous chemicals. Cells are incubated with nutrition medium supplemented with the gaseous substances to be tested. These methods are not feasible for the examination of toxic gases, which are insoluble in water. Carbon monoxide (CO), a poorly soluble and toxic gas (lethal dose 1 vol% for some minutes) has been chosen as a model gas. Besides its binding to hemoglobin, it also leads to an inhibition of cytochrome c oxidase in the mitochondrial respiratory chain of living cells. Thus, a decrease in the respiratory behavior of eukaryotic cells indicates the presence of CO in a gaseous phase. Based on the Bionas® 2500 analyzing system, a device to measure the metabolic and morphological effects, caused by direct gas exposure on eukaryotic cells was established. The gaseous substances directly contact the eukaryotic cell line V79 (Chinese hamster lung fibroblast) without interfering liquid phase in between. Beside the measurement of oxygen consumption also acidification and impedance changes of the cell culture are detected by a metabolic sensor chip. In order to increase the stability different chip surface coatings like collagen A and poly‐L‐lysin (PLL) were used. Adhesion coating leads to a tighter junction of the cells to the sensor chip surface and thus enables higher stability of the confluent cell monolayer towards the gaseous flow during the gas exposure. The method reported here has the potential to become a valuable means for rapid monitoring of toxic compounds in gaseous phases.