UCLA

Over 1300 consumer products currently on the market contain nanoparticles (NPs); among them, metal-containing NPs constitute the largest class. In this research, high-throughput spectrophotometric methods, microscopy, chemical analyses, and genetic studies were used to describe interactions between copper NPs and model freshwater microalga, Chlamydomonas reinhardtii. A newly-developed HTS algae viability assay was used to measure IC50 concentrations of 20-25 mg/L Cu NPs for C. reinhardtii cells. While Cu NPs were toxic to algae at excess concentrations, these algae cells were able to utilize the copper as a nutrient under deficient conditions. The data indicate that NP toxicity was primarily due to release of copper ions, but ROS generation, heat and light responsive cellular systems, and osmotic burst were also likely mechanisms of Cu NP-mediated cell death.