纳米金颗粒增强的痕量汞光声检测机理与方法研究

Soluble mercury ion is one of the commonest heavy metal ions, which has high cytotoxicity, corrosiveness and carcinogenicity to human bodies. However, the existing detecting method of trace mercury ion has several disadvantages, such as expensive equipment, strict preservation conditions and long operation time. A new photoacoustic detection method enhanced by gold nanoparticles (Au NPs) was proposed in this proposal which can realize on-line, selective detection of trace mercury by use of surface-functionalized Au NPs. In this proposal, the synthesis method of Au NPs in trace photoacoustic detection as well as the impact of Au NPs on the detection sensitivity will be researched. The surface modification methods and the interaction mechanism between surface modified materials and mercury ion will be analyzed. The miniature photoacoustic detection experiment system will be set up, and the mechanism of mercury concentration detecting based on photoacoustic method will be studied. Finally, a set of Au NPs-enhanced photoacoustic detection system for trace mercury ion detection will be established. The measurement accuracy can be better than 5 nmol/L. The proposed method will lay the foundation for the realization of universal trace mercury ion detector in the future.

可溶性汞离子是一种常见的重金属离子，对生物系统具有极强的细胞毒性、腐蚀性和致癌性。在很多环境条件下汞离子浓度的检测精度要求已达到痕量甚至超痕量级，而水体中又常常混杂大量其他污染物成分，汞离子污染事件常常具有很强的突发性和随机性，因此如何同时满足痕量汞的高灵敏度、高选择性、高速度、小型化、低成本等多个方面的要求，已成为急需攻克的难题。本项目针对痕量汞在线检测的实际需求，提出纳米金颗粒增强的液体痕量浓度光声检测的新思路，揭示汞离子浓度变化对纳米金颗粒聚集程度的影响机制，阐明纳米金颗粒尺寸和形状等对光声测量灵敏度的影响机理与规律，建立优化设计理论模型与准则，提出精准的光声信号特征值自适应提取方法，构建完整的纳米金颗粒增强光声测量理论体系，研制微量型液体痕量检测仪实验样机，痕量汞离子检测精度优于5nmol/L，为最终能够实现高精度、高速度、高速度、低成本的痕量汞在线检测奠定基础。

可溶性汞离子是一种常见的重金属离子，对生物系统具有极强的细胞毒性、腐蚀性和致癌性。为了实现汞离子浓度的痕量甚至超痕量级特异性测量，本项目提出纳米金颗粒增强的液体痕量浓度光声检测方法，完成了纳米金材料的光谱性质、聚集性质以及表面亲和性研究并选用了高效的表面修饰物质，完成了液体光声检测理论研究，提出了光强温度双补偿算法，并搭建了可适用于所有非腐蚀性的液体的汞离子检测平台，对汞离子开展了灵敏度、特异性、复杂环境等多项测试，实验结果表明，此方法对汞离子的检测灵敏度高达78pmol/L, 同时能够抑制铅离子、铬离子等十余中种重金属离子的干扰。