鉴于新型纳米材料氧化石墨烯具备环境暴露风险高、反应活性强、纳米缺陷多及比表面积大等特点，开展其在水体中协同或拮抗高致毒物砷的生物有效性及其分子机制研究至关重要。由于污染物形态决定其生物有效性, 课题首先采用高效液相色谱串联电感耦合等离子体质谱、电子顺磁共振和傅里叶转换红外光谱技术等，从水体砷价态重构、自由基生成、络合态分子结构及纳米缺陷作用位点角度，阐明氧化石墨烯重构水体砷的形态及其化学机制。进一步，课题选择普通小球藻作为模式生物，采用快速细胞分析仪、透射电镜-能谱仪和膜片钳技术等，从生物生长发育、细胞形貌结构、复合污染物胞内迁移分布及离子通道功能角度，揭示氧化石墨烯重构砷诱发的生物效应。最后，课题借助高通量生物分析技术，通过搭建活性氧-基因-蛋白-代谢物与生物效应的因果关系，揭示生物有效性重构的分子机制。该研究将为科学评估氧化石墨烯复合生态风险及新形势下砷的生物有效性提供理论技术支撑。

Graphene oxide (GO) as an emergent nanomaterial exhibits high risks of environmental exposure, strong reactivity, lots of nano defects and large specific surface area, etc. Therefore, it is critical to carry out the study of bioavailability and molecular mechanisms for the synergistic or antagonistic reactions between GO and high-toxicity pollutant (arsenic). Given that the speciation of pollutants determines their bioavailability, the valence state reconstruction of aquatic arsenic, the generation of free radicals, the molecular structures of complex state and the reactive sites of nano defects are studied to reveal the reconstructions of arsenic speciation and its chemical mechanisms using the high performance liquid chromatography tandem inductively coupled plasma mass spectrometry, electron paramagnetic resonance and Fourier transform infrared spectrum techniques. Furthermore, the Chlorella vulgaris is selected as the model organism. The growth and development of organisms, the morphology and structure of cells, the translocations of complex contaminants and the functions of ion channels are analyzed to illuminate the biological effects of arsenic reconstructions using rapid cell analyzer, transmission electron microscopy-energy dispersive and patch-clamp techniques. Finally, the relationships among the reactive oxygen species-genes-proteins-metabolites are established using high-throughput analysis to reveal the molecular mechanisms of bioavailability reconstruction. The study will provide theoretical and technical suggestions for the scientific assessment of GO joined-ecological risks and bioavailability of arsenic on new conditions.