Similar toxicity mechanisms between graphene oxide and oxidized multi-walled carbon nanotubes in Microcystis aeruginosa

In photosynthetic microorganisms, the toxicity of carbon nanomaterials (CNMs) is typically characterized by a decrease in growth, viability, photosynthesis, as well induction oxidative stress. However, it currently unclear how shape structure CNMs, such 1-dimensional nanotubes (CNTs) compared to two-dimensional graphene oxide (GO), affects way they interact with cells. this study, effects GO and oxidized multi-walled CNTs were cyanobacterium Microcystis aeruginosa determine similarities or differences two CNMs induce cyanobacteria. Using change Chlorophyll concentrations, effective concentrations inducing 50% inhibition (EC50) at 96 h are found be 11.1 ?g/mL 7.38 for CNTs, respectively. The EC50 not statistically different. Changes fluorescein diacetate 2?,7?-dichlorodihydrofluorescein fluorescence, measured suggest esterase enzyme activity but no Scanning transmission electron microscopy imaging did show extensive membrane damage cells exposed CNTs. Altogether, metabolic without stress support hypothesis that both induced indirect through physical mechanisms associated light shading cell aggregation. This explains why intrinsic shape, size, surface properties between result