Relationships Between the Properties of Metal-based Nanoparticles with Different Particle Sizes and Their Environmental Behaviors and Biological Responses

With the rapid development of nanotechnology, relationships between the varying physicochemical properties of metal-based nanoparticles (MNPs) and their environmental behaviors or biological responses have recently received intensive attentions from researchers and policy makers. Due to the unique physiochemical properties, MNPs have been applied in various fields including agriculture, chemistry, aerospace and so on. This inevitably leads to their release into the environment, posing a great threat to environmental living organisms or even the human health. With the decrease of particle size, the properties of MNPs can be also altered such as showing a larger specific surface area, an increased surface charge density and surface energy as compared with bulk materials, which greatly affects the interface reactions and biological effects of MNPs. This paper thus reviewed the relationships between the specific surface area, the surface functional groups, the surface energy or the surface charge density of MNPs at different particle sizes and their environmental behaviors such as adsorption, aggregation and dissolution. The biological effects and the underlying mechanisms of MNPs at different particle sizes were deeply analyzed under different environmental conditions (e.g. dissolved organic matter (DOM), illumination, pH value and ionic strength). Some suggestions were put forward to improve the existing research. © 2021, Materials Review Magazine. All right reserved.