Analysis of cell viability/cytotoxicity
After cell treatments for 48h, chips were rinsed with PBS and incubated at RT for 1h with blue-fluorescent nuclear dye Hoechst 33342 (5 μg/mL in PBS) that stains all nuclei, and the red-fluorescent dye EthD-1 (4 μM in PBS) that is selective to nuclei of dead cells. The number of deadvs. total cells laying in each cell culture microchamber was visualized under a laser scanning confocal microscope (Nikon A1R) and counted through an automated measurement routine (NIS Elements AR). Results were plotted as a percentage of live cells in FFAs- and polyphenols- treated vs. control cultures.