Improved cell sensitivity and longevity in a rapid impedance-based toxicity sensor

A number of toxicity sensors for testing field water using a range of eukaryotic cell types have been proposed, but it has been difficult to identify sensors with both appropriate sensitivity to toxicants and the potential for long-term viability. Assessment of bovine pulmonary artery endothelial cell (BPAEC) monolayer electrical impedance with electric cell-substrate impedance sensing (ECIS) showed promise in a previous systematic evaluation of toxicity sensor technologies. The goal of the study reported here was to improve toxicant responsiveness and field portability of this cell-based toxicity sensor. A variety of human cells, non-human mammalian cells, and non-mammalian vertebrate cells were screened for sensitivity to 12 waterborne industrial chemicals. The results of this assessment show that bovine lung microvessel endothelial cell (BLMVEC) monolayers and iguana heart (IgH-2) cell monolayers could detect nine out of the 12 waterborne industrial chemicals, an improvement over the seven chemicals previously detected using BPAEC monolayers. Both the BLMVEC and IgH-2 cell monolayers were tested for their ability for long-term survival on the ECIS test chips in a laboratory environment. Both cell lines were able to maintain high impedance readings on the ECIS electrodes for 37 days, a key trait in developing a field-portable toxicity sensor for water. Cell line optimization has greatly contributed to the on-going development of a field-portable cell-based biosensor that detects with sensitivity a wide range of waterborne toxicants.