0.4 mM TPA and 0.667 g L−1 nanoparticles (MT 500 SA)) was irradiated under the artificial solar light (light intensity of 45 mW cm−2) for 0, 5, 10, 20, 40, 60 and 90 min. Particles were filtered through a 0.1 μm filter and fluorescent intensity was measured using Fluorimeter (RF-1501) (Shimadzu).