Implications of “Trap Emission ” Observed from Quantum Dot Nanoparticles Accumulated in Toxicity Test Organism, Daphnia magna

Despite the great achievements in nanosciences and nanotechnologies, there are increasing concerns about their potential harmful effects on our environment and human health.1 Therefore, increasing number of studies on the toxicities of engineered nanomaterials have been published during last few years and understanding their environmental fates and biological impacts became one of the urgent scientific and social issues to be addressed in near future. Quantum dots (QDs) are semiconductor nanocrystals (NCs) with size-dependent optical properties, which have great potential in many application areas, such as solar cells, light-emitting devices, biological and medical imaging.2 However, increasing concerns for potential QD toxicities are raised recently, due to its unknown toxicity as a nanometer-scale material as well as the well-known toxicity of it