Fig 4. UV-light power effect (different excitation slit openings) on EGF photochemistry: A) EGF fluorescence excitation and emission wavelengths were fixed at 295 nm and 330 nm, respectively, for 0.1 mm (0.12 μW), 0.5 mm (0.30 μW), 0.8 mm (1.67 μW), 1.2 mm (2.34 μW) and 2.0 mm (4.40 μW); B) SYPRO^® Orange fluorescence excitation and emission wavelengths were fixed at 470 nm and 580 nm, for the same power levels.

Continuous illumination was conducted during 2 hours and the temperature of each solution was kept at 20°C for all experiments.