An Assessment of the Impact of SiO2 Nanoparticles of Different Sizes on the Rest/Wake Behavior and the Developmental Profile of Zebrafish Larvae

In this study, zebrafish larvae are introduced as an in vivo platform to examine the neurotoxicity and developmental toxicity associated with continuous exposure to a concentration gradient of different sizes of SiO2 nanoparticles (15 nm and 50 nm diameter) to determine the dose effect and size effect of SiO2 nanoparticle (NP)-induced toxicity. Bovine serum albumin (BSA-V) is utilized as a stabilizing agent to prevent coagulation of the SiO2 nanoparticles. To the best of our knowledge, this study is the first to describe locomotor activity assays linking rest/wake behavioral profiles for the purpose of investigating the neurotoxicity of NPs. In addition, developmental toxicological endpoints including mortality, LC50 , malformation, and cartilaginous deformity are assessed. The results show a concentration-dependent increase in behavioral neurotoxicity, mortality, and malformation among larvae treated with the SiO2 nanoparticles of 15 nm and 50 nm. A comparison of the 15 nm and 50 nm NPs by K-means clustering analysis demonstrates that the 15 nm NPs have a greater neurotoxic effect than the 50 nm NPs, with the 50 nm NPs exhibiting greater developmental toxicity on the zebrafish larvae than the 15 nm NPs.