Fig. 5From: Bactericidal effects of 310 nm ultraviolet light-emitting diode irradiation on oral bacteriaProduction of nitric oxide in Ca9–22 cells by irradiation with the 310 nm UVB-LED. a Monolayers of Ca9–22 cells were irradiated with 310 nm UVB-LED for 60 s and incubated for 24 h. Nitric oxide production into cells was then examined using DAF2-DA. b The level of fluorescence was expressed by using Image J. (n = 3, means ± SE; **P < 0.01)Back to article page