Figure 3.

Alteration of Cell Viability and ROS Expression Induced by 660-nanometer LED Irradiation. (A) Cell viability (%) analyses after 24 h of 660-nanometer LED irradiation with a power of 10 mW/cm² and various total energies (3, 6, 12 and 18 J/cm²). Results showed that there were no significant effects on overall cell types at any power density (p > 0.05; n = 9); (B) Representative images of the ROS assay (FITC) (scale bar: 100 μm); (C) The intensity of ROS-positive (FITC+) cells was significantly increased by LED irradiation (Ctrl vs. 660 nm; n = 48 vs. 57, ** p < 0.01).