基于各向异性金属纳米晶液相可控生长与蚀刻的LSPR传感新方法研究

Metal nanoparticles with excellent localized surface plasmon resonance (LSPR) properties have been widely used in biochemical analysis and imaging. However, the mechanism, influences of particle shape as well as the shape evolution in the analysis toward the analytical sensitivity and selectivity, is not clear yet. Thus, the application of metal nanocrystals with anisotropic structures in analytical chemistry is limited. The present proposal intends to systematically study the kinetic and thermodynamic parameters in the synthesis of metal nanocrystals in liquid phase, and thus develop simple and efficient syntheses to control their shapes and structures. Then, using the anisotropic metal nanocrystals as analytical probes, we will control the evolution of their shape, size, and composition based on the principles of seed-mediated epitaxial growth and facet-selective oxidative etching. The aim of this proposal is to clarify the relationship between the obtained LSPR signal and the shape evolution of metal nanoprobes in analysis, and optimize the shape of LSPR probes according to different requirements for applications. In this case, a series of highly sensitive and new LSPR sensing methods can be developed for biomedical purpose. Understanding the scientific questions proposed here will enable us to consummate the theory related to the LSPR control by the structure of metal nanoprobes, and also develop practical methods for biomedical analysis. This project is worth studying in theory and also promising for practical applications.

金属纳米探针的局域表面等离子体共振(LSPR)性质已广泛应用于生化分析，但探针自身形貌特征及其在分析过程中的演变对方法灵敏度和选择性的影响机制尚不清楚，使各向异性结构的金属纳米探针在分析化学中的应用受到局限。本项目拟通过探讨液相法合成金属纳米晶的动力学和热力学影响因素，发展简单、高效的合成新方法以实现探针各向异性形貌的精细调控，在此基础上借助晶种介导外延生长和晶面选择性氧化蚀刻的原理在分析过程中控制探针形貌、尺寸、元素组成等参数发生定向改变，揭示探针自身形貌及其演化规律与分析信号获得之间的构效关系，实现不同需求下的探针形貌最优化控制，建立面向生物医药的高灵敏LSPR传感新方法。项目凝练出如何阐明探针形貌及其演化规律与分析灵敏度、选择性之间的内在联系这一关键科学问题，旨在完善各向异性结构金属纳米探针的LSPR调控机制，并建立实用的生物医药分析新方法，既有理论价值又有应用前景。

金属纳米探针因其可调的局域表面等离子体共振(LSPR)性质已在分析传感领域得到广泛应用。本项目以各向异性金属纳米晶为主要研究对象，以纳米晶的形貌结构及其光学性质的精准调控作为研究主线，开发出了一系列具有可调光学信号和实际应用前景的新型纳米探针并将其应用于生物传感和疾病诊疗。按照预期计划，项目取得了以下主要进展：. 1.通过调控反应过程中的热力学和动力学因素，设计并制备了一系列不同形貌结构（如褶皱片状、褶皱“纸团”状、立方体形“蛋黄-蛋壳”结构及空心盒子等）和元素组成（单金属、双金属及三金属）的各向异性纳米晶，并对其成核与生长机理进行了详细探讨。. 2.通过理论模拟和实验手段探讨了具有复杂结构和元素组成金属纳米晶的物理特性参数对其LSPR吸收、散射及LSPR增强的光热转换性质的影响及机制。. 3.基于晶种介导生长和选择性蚀刻两种原理调控纳米探针的形貌结构、表面化学或元素分布发生定向改变，实现了其光学吸收和光热转换性质的有效调节，根据目标待测物直接或间接导致的信号变化构建了一系列简便、快速和高灵敏度的光学分析新方法。. 4.将开发的新型纳米探针和光学分析新方法进一步成功应用于生物活性分子、小分子药物的检测及重要疾病的诊疗中。