Zinc oxide nanomaterials (nano-ZnO) are emerging pollutants that have been used in a variety of industrial processes, from productions of rubber, pharmaceutical and cosmetic products, to applications in electrotechnology. However, the high usage of nano-ZnO has raised the concerns of potential environmental risks. Previous studies demonstrated that nano-ZnO could cause toxicity to aquatic organisms and the toxicity were mainly contributed by the dissolved Zn²⁺. Thus, identifying the dissolution kinetics is important in ecotoxicological research regarding nano-ZnO. In light of the limitations of currently available methodologies, we developed a new fluorescence method to monitor the dissolution kinetics of nano-ZnO in a real-time scale. The proposed fluorescence method was proved to...[ Read more ]

Zinc oxide nanomaterials (nano-ZnO) are emerging pollutants that have been used in a variety of industrial processes, from productions of rubber, pharmaceutical and cosmetic products, to applications in electrotechnology. However, the high usage of nano-ZnO has raised the concerns of potential environmental risks. Previous studies demonstrated that nano-ZnO could cause toxicity to aquatic organisms and the toxicity were mainly contributed by the dissolved Zn²⁺. Thus, identifying the dissolution kinetics is important in ecotoxicological research regarding nano-ZnO. In light of the limitations of currently available methodologies, we developed a new fluorescence method to monitor the dissolution kinetics of nano-ZnO in a real-time scale. The proposed fluorescence method was proved to be a more simple, cost-effective and suitable method for the real-time monitoring of dissolution kinetics of nano-ZnO as compared to the commonly adopted practice, namely inductively coupled plasma mass spectrometry (ICP-MS) method. After investigating the environmental behaviour of the nano-ZnO, focus was put on the toxicological impacts of nano-ZnO. In order to understand the toxicological impacts of nano-ZnO deeply, we adopted a cell line as the model. Results showed that nano-ZnO showed less cytotoxicity, but higher bioavailability as compared to the ionic Zn towards the embryonic zebrafish fibroblast cell line (ZF4).