Effects of representative quantum dots on microorganisms and phytoplankton: a comparative study

Abstract

With the increasing application of semiconductor particles, especially metal-based quantum dots and carbon quantum dots (CQDs), these quantum dots will inevitably be released into the environment, and therefore their effects on biota should be assessed. Few studies on the effects of CQDs on microorganisms and phytoplankton have been performed. In this paper, we put forward more effective and convenient approaches to prepare three kinds of high-quality CQDs. Then we assessed their effects on Staphylococcus aureus and Microcystis aeruginosa, which were representative of microorganisms and phytoplankton, respectively, and compared the effects with the effects of metal-based QDs (CdSeQDs or CdTe-QDs). The results showed that CQDs at low concentrations (<50 mg L À1 ) had insignificant effects on the growth of Staphylococcus aureus and Microcystis aeruginosa, while the influence of the CQDs was observed significantly when the concentration was increased up to 100 mg L À1 . However, the negative impact of metal-based QDs was observed at any given concentration. In conclusion, the results demonstrated that any kind of carbon quantum dot has lower ecological risks than metal-based QDs, which may provide a reference for utilizing carbon quantum dots better and safely.

Effects of Carbon Quantum Dots on Aquatic Environments: Comparison of Toxicity to Organisms at Different Trophic Levels

“…aeruginosa and C. pyrenoidosa. , For the first time, the present study investigated effects of CQDs on the growth of S. obliquus.…”

“…CQDs treatments inhibited growth and induced oxidative damage in Chlorella pyrenoidosa . Similarly, treatments with 100 mg/L of CQDs significantly inhibited cell growth and decreased the chlorophyll-a content in Straphylococcus aureus and Microcystis aeruginosa . These results suggested that algae might be more sensitive to CQDs than fish.…”

“…Carbon-based nanomaterials (e.g., graphene, graphene oxide, carbon nanotubes, fullerenes, and CQDs) are fabricated on a large scale and represent the second-most referenced nanomaterials in commercial products. ,, However, there is a general lack of data on the environmental effects and ecosystem risks of carbon nanomaterials, with particular shortages in the aquatic toxicity of CQDs. Although a few studies have evaluated the effects of CQDs on a single aquatic species, ,, these studies varied widely in the source and properties of CQDs or did not offer systematic characterization of the structure and composition of nanoparticles. In the present study, comprehensive characterization of CQDs and the impacts of CQDs on three aquatic organisms (zebrafish, D.…”

“…19 Similarly, treatments with 100 mg/L of CQDs significantly inhibited cell growth and decreased the chlorophyll-a content in Straphylococcus aureus and Microcystis aeruginosa. 20 These results suggested that algae might be more sensitive to CQDs than fish. To assess whether CQDs are toxic to aquatic ecosystems, studies and comparisons of CQDs-induced effects on aquatic organisms at different trophic levels should be conducted.…”

ECOTOXICOLOGICAL BIOASSAYS IN QUANTUM DOTS NANOPARTICLES WITH THE MICROALGAE Pseudokirchneriella subcapitata

“…With the increasing application of semiconductor particles, especially metal-based QDs, these quantum dots will inevitably be released into the environment, and therefore their effects on biota should be assessed. Few studies on the effects of QDs on microorganisms and phytoplankton have been performed (Yan et al 2015a). A novel sensing system has been designed for the detection of m-phenylenediamine based on carbon QDs improved chemiluminescence in a luminol-potassium permanganate (KMnO 4 ) system.…”