2 × 104/ml cell suspension fluid was inoculated in 96-well plates, with each well having 3 parallel wells and about 100 μl fluid, and cultured in an incubator with 5% CO2 at 37°C to 24, 48, 72, 96 h, respectively. Following that, the plates were taken out, added with 50 μl MTT solution each well that was configured into 1 g/L with normal saline, and incubated at 37°C for 4 h to discard the supernatant fluid, then added with dimethylformamide (DMSO) (100 μl per well), shaken for 10 min to fully resolve MTT pyrolysis products. Optical density (OD) was measured by immunoassay analyzer at the wavelength of 570 nm, drawing cell growth curve.