MTT Assay for Cell Viability

Cell viability was assessed by a methyl-thiazoldiphenyl-tetrazolium (MTT) assay (MTT Cell Growth Assay Kit, Chemicon, Rosemont, IL, USA) [19 (link),21 (link),22 (link)]. We seeded hDPSCs at a density of 1.0 × 10⁴ cells/well on 24-well cell culture plates (SPL Life Sciences, Pocheon, Korea). The material disks were placed into inserts with a 0.4 μm pore size (SPLInsert; SPL Life Sciences), and these inserts were maintained over the attached hDPSCs for 5 days. Then, the hDPSCs were treated with MTT solution according to a previously reported method at 0, 1, 2, 3, and 5 days [19 (link)]. We measured the absorbance at 570 nm. Positive controls were hDPSCs cultured without experimental disks. Each group was evaluated in quadruplicate.