Evaluation of nanoplastics-induced redox imbalance in cells, larval zebrafish, and daphnia magna with a superoxide anion radical fluorescent probe

Nanoplastics (NPs) is a novel plastic contaminant that could be taken up by cells and lead to severe biotoxicity toxicity, NPs in cells can cause oxidant damage by inducing reactive oxygen species (ROS) production and lead to acute inflammation. As a major ROS which related to many kinds of physiological and pathological processes, superoxide anion radical (O2•−) could be utilized as a signal of oxidant damage effected by NPs exposure in vivo. To detect the toxic damage mechanism of NPs, a fluorescence probe Bcy-OTf has been developed to monitor O2•− fluctuations content in cells and aquatic organisms after exposure to NPs. The probe has a high sensitivity (LOD = 20 nM) and a rapid responsive time (within 6 min), and it has high selectivity and low cytotoxicity to analysis the levels of the endogenous O2•−. Endogenous O2•− induced by NPs in living cells, Daphnia magna and larval zebrafish were analyzed. Moreover, the results confirmed the key role of MAPK and NF-κB pathway in NPs stimulation mechanisms in cells. This study indicated that Bcy-OTf can precisely assess the fluctuations of endogenous O2•−, which has potential for applying in further analysis mechanisms of NPs biological risks.