基于纳米示踪技术解析双酚S在褐牙鲆体内发挥甲状腺干扰效应的作用靶点

褐牙鲆是我国北方沿海重要的增养殖鱼种，其早期发育会经历由甲状腺激素(THs)调控的变态过程。课题组前期发现环境浓度双酚S(BPS)能改变甲状腺滤泡结构、降低THs水平，对褐牙鲆的变态造成潜在危害。为解析BPS降低THs的根本原因，本项目拟利用抗体与纳米材料构建BPS的示踪技术，寻找BPS干扰甲状腺系统的靶点。制备BPS单克隆抗体、合成发射光谱相近的金纳米颗粒与量子点，借助抗原-抗体反应将两种纳米材料结合到BPS上，利用激光共聚焦显微镜观察细胞内BPS的分布；基于石墨烯/金纳米复合材料构建准确定量组织中痕量BPS的电化学免疫传感器。利用以上方法解析BPS在甲状腺轴线相关组织及细胞内的吸收、转运、蓄积过程，结合BPS诱导的生物学效应，建立BPS污染与甲状腺干扰之间的关联，确定BPS的作用靶点。该研究能够阐明BPS降低褐牙鲆THs水平的根本原因，为解析污染物对海洋鱼类的毒性作用机理提供新的视角。

Japanese flounder (Paralichthys olivaceus) is an important aquaculture species in northern coastal areas of China and its larvae undergoes metamorphosis which is mainly regulated by thyroid hormones (THs). Our previous study found that exposure to environmental concentrations of bisphenol S (BPS) changed the histological structure of thyroid follicles and decreased the level of THs, and thereby would disrupt the metamorphosis of Japanese flounder. To illuminate the root cause of reduced THs levels caused by BPS, this project aims to investigate potential targets of BPS in the thyroid axis of Japanese flounder using tracer technologies based on the antibody and nanomaterials. Firstly, anti-BPS monoclonal antibody is prepared, and gold nanoparticles and quantum dots with similar emission spectra are synthesized. Then, these two nanomaterials will be combined to BPS through antigen-antibody reaction, and the intracellular locations of BPS are observed by using laser confocal microscope. Moreover, using graphene/Au nanocomposites and anti-BPS monoclonal antibody, a sensitive electrochemical immunosensor for BPS will be established. Based on these two techniques, the absorption, transport and accumulation of BPS in the brain, thyroid and liver of Japanese flounder will be determined. Meanwhile, the damage of tissues and cells, and changes of crucial hormones, enzymes, and genes in HPT axis are measured. The association between BPS and disruption of THs will be further established and used to determine the targets of BPS. The results will clarify the basic reason for the decrease of THs after BPS exposure and provide a novel insight for studying the toxic mechanism of pollutants on marine fish.