*2.7. Cell Viability Assay (MTT)*

MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) at 5 mg/mL−<sup>1</sup> was added on A549 cells cultured in 96-well plate at a density of 5000 cells per well. Following 1 h incubation, MTT medium was removed and the insoluble formazan was solubilized with 100 μL of DMSO. Absorbance of converted dye was measured at 570 nm with a background subtraction at 690 nm.
