基于纳米金氧化溶出机理的小分子环境污染物的可视化分析方法研究

Several small molecular environmental pollutants confer enormous risk to human health, such as bisphenol A with reproductive toxicity and carcinogenicity, and hypochlorite which plays a critical role in the human immune system and cause cardiovasular diseases, neuron degeneration and cancer. In spite of the perfect sensitivity and reliability of traditional environmental analytical methods, the expensive instruments, complex pretreatment procedures and strict determination conditions have limited their application in environmental analysis to some extent. Therefore, it is necessary and urgent to develop a cheap, facile and rapid analytical method for these pollutants. Based on the previous work on colorimetric detection technology, this project proposes a colorimetric assay for bisphenol A and hypochlorites utilizing an oxidative reaction system between pollutants and gold nanoparticles, established with the self-synthesized gold nanorods (AuNRs) as the nanoreactor and color reader. Based on the surface plasmon resonance absorption and color-changing of the AuNRs solution, the determination of small molecular pollutants with colorimetric method can be realized. The oxidative etching effect of pollutants toward AuNRs will be explored and a test colorimetric paper which is suitable for rapid monitoring of target pollutants in large quantities of environmental water samples will be developd. The achievements of this project can be expected to broaden the application of colorimetric technology in the analysis of small molecular pollutants, promote the development of the colorimetric detection theory, as well as with great academic value and application prospect.

某些小分子环境污染物严重危害人类的身体健康，例如双酚A具有生殖毒性和致癌性，次氯酸盐可参与人体免疫系统，诱发心血管疾病和癌症等。传统的环境分析方法虽然具有很好的灵敏度和可靠性，但仪器价格昂贵、样品前处理复杂、分析条件苛刻等一定程度上限制了其在环境分析中的应用，因此亟待建立一种仪器简单、操作简便快速的小分子环境污染物分析方法。基于以往可视化分析技术的研究基础，本项目以次氯酸盐和双酚A为研究对象，提出利用自制金纳米棒建立纳米金与污染物的氧化析出反应体系，依据纳米金表面等离子体共振吸收和溶液颜色变化实现小分子污染物的可视化分析检测，阐明目标污染物对纳米金氧化析出的调控机理，并试制适合大批量环境水样中目标污染物快速监测的试纸。研究成果能够为可视化分析技术在小分子环境污染物检测领域的拓展提供新思路，促进可视化分析理论的发展，具有重要的学术意义和应用价值。

本项目围绕贵金属/金属氧化物纳米材料在污染物可视化分析检测及吸附去除中的应用展开。通过种子介导方法合成金纳米棒，具有强氧化性的次氯酸钠引起金纳米棒的氧化溶出刻蚀反应，减小金纳米棒的纵轴长度及纵横比。依据胶体溶液的纵轴表面等离子体共振（LSPR）吸收和溶液颜色发生变化，实现自来水中余氯的直接定量检测。通过与国标方法对照，该方法的准确度达到8.53%以上。以没食子酸功能化纳米银为纳米反应器和基质，建立了一步法快速检测钴离子的可视化技术，该检测实验可以在5分钟内完成，并且实验过程完全“绿色”，无需添加任何有毒试剂或溶剂。制备聚多巴胺包覆的磁性纳米材料(Fe3O4@PDA NPs)，通过控制变量获得最佳吸附实验参数，并以其为磁性吸附剂，实现了模拟废水和自来水中铅离子的净化去除，为铅污染环境水样的净化处理提供新的实验策略。通过共沉淀法制备磁性吸附剂(Fe3O4@GA NPs)，并考察其对重金属铅的吸附行为研究，该吸附剂重复利用三次后，对铅的去除效率仍然达到90%以上。Fe3O4@GA NPs具有制备过程简单、无需使用高温、有毒试剂等特点。