4.2. Measurement of Cell Viability

Cell viability was measured by the MTT assay. Briefly, after drug treatment for 24 h, 5 mg/mL MTT solution (10 μL) was added to each well. After incubating at 37 °C for 4 h, 100 μL solvating solution (0.01 N HCl, 10% SDS) was added, and incubated for 20 h. The absorbance of the samples was measured at a wavelength of 570 nm with 655 nm as a reference wavelength.