DESI-HRIMS-TOFMS原位表征金纳米团簇液相反应体系的新方法

It is significance to on-site monitor the formation process of nano cluster and there are no effective techniques and methods. Mass spectrometry is the gold standard for the identification the mass and the structure of the compounds due to its ability of full spectra anslysis. But current mass spectrometry combined with laser desorption/ionization source or electrospray ionization source cannot monitor the profile of nano cluster; ion mobility-mass spectrometry cannot identify the cluster isomer due to the low resolution of ion mobility. This project aimed at the new method on the time evolution and the precision structure analysis of Thiol-protected Au nano cluster based on desorption electrospray ionization-high resolution ion mobility-time of flight mass spectrometry. It mainly includes: to develop high efficiency desorption electrospray ionization source to on-site ionize/sample/analysis of nano cluster; The isomers in nano cluster will be identified via ion mobility spectrometry with high resolution higher than 200 and the model of nano cluster struncture and collision cross section will be set up; The time evolution of nanocluster with the change of reaction time and environment parameters will be studied based on the instrument with time-resolution of seconds level and the critical parameters and critical species will be confirmed, which help the construction of the nano cluster with special functions.

纳米团簇制备过程的表征对于功能团簇的构建具有重要意义，缺乏原位在线表征技术和方法。质谱可实现全谱分析、是鉴定団簇分子量及构成的金标准；高分辨离子迁移谱可实现团簇同分异构体的有效分离。本项目拟以硫醇保护的金纳米团簇这一热点体系为对象，基于解吸电喷雾电离-超高分辨离子迁移-高精度飞行时间质谱的建立纳米团簇全谱在线表征新方法，深入研究液相反应体系中団簇结构、大小及同分异构体的变化规律：发展新型解吸电喷雾离子源对液相纳米団簇原位电离、解吸进样；基于200分辨的超高分辨离子迁移谱实现纳米金団簇同分异构体分离表征，建立団簇结构与碰撞截面的关联模型，精准确定团簇结构特征；基于秒级时间分辨的平台开展金纳米团簇液相体系演变特性研究，建立和完善纳米団簇全谱表征的新方法，研究制备参数等对纳米団簇的影响规律，确定団簇调控的关键参数和关键物种，为功能型纳米団簇的构筑提供参考。

纳米团簇制备过程的表征对于功能团簇的构建具有重要意义，缺乏原位在线表征技术和方法。质谱是鉴定団簇分子量及构成的金标准，有助于对制备过程和产物进行精准标准。本项目针对金纳米团簇这一热点对象，建立了纳米团簇的表征方法，并对水相法和油相法合成的金纳米团簇进行了系统表征研究。具体包括：搭建了用于团簇电离和原位表征的电喷雾电离-高分辨离子迁移管，其分辨率可以达到210以上；基于油相法制备的金纳米团簇，利用高分辨质谱对不同阶段的产物演变开展了检测，激光解吸电离质谱的激光能量的增加有助于观测到大质量数离子，且基质的引入有助于提升检测的灵敏度；基于水相法制备了金纳米团簇，由于极性基团的存在容易形成多电荷的产物离子，利用同位素丰度的分布可以推断离子所带电荷数量，进而推断团簇的结构和组成，由于大质量数金纳米团簇可携带多电荷有利于大质量数团簇的传输和检测灵敏度。本项目开展了不同反应体系制备纳米金团簇的相关研究，并研究了不同反应阶段和产物离子的演变规律，为纳米团簇的表征提供了参考和依据。在Nano-Scale、Analytical Chemistry等专业期刊发表研究论文8篇，申请发明专利3项。