量子点近红外电致化学发光及其成像研究

Quantum dots have become a very compelling research focus on the field of luminescence as a new kind of electrogenerated chemiluminescence (ECL) reagent. The main propose of this project is to develop and improve the quantum dot near-infrared electrogenerated chemiluminescence (NECL) systems, and to enrich quantum dots ECL theories. To develop new strategies for the synthesis of near-infrared quantum dots, series of high-quality near-infrared quantum dots are prepared by surface state regulation, band alignment staggering/compressing or ingredients doping methods. The relationship between the surface states of quantum dots and the main NECL models together with their intensity are systematically investigated. The effects of electron-hole spatial separation in core-shell quantum dots and the delocalization degree of exciton in crystal surface, on the excite potential and electron/hole transport efficiency are deeply discussed. The basic regulations of quantum dot NECL are revealed in detail. On this basis, intelligent NECL sensing interface is built by means of homogeneous reactions, magnetic enrichment and the amphiphilic silica carriers. The effects of some factors such as light-emitting unit intensity, the size of horizontal light-emitting interface and assembly efficiency of vertical interfaces, on NECL imaging signals are also systematically studied. A NECL imaging diagnostic platform based on quantum dots is created by using porcine transmissible disease biomarkers as a model, which can not only be used for highly sensitive and in situ analysis of complex biological samples, but also provide an important way for the on-site detection of the animal diseases.

量子点作为一类全新的电致化学发光（ECL）试剂，已成为发光领域十分引人注目的研究热点。本项目以发展和完善量子点近红外电致化学发光（NECL）体系、丰富量子点ECL理论为目标，发展近红外量子点的合成新策略，通过表面态调控、能级交错/挤压、成分掺杂等手段，制备系列高质量近红外量子点；系统研究量子点NECL主要形式、发光强度与量子点表面态的关系；深入探讨核壳型量子点中电子-空穴空间分离、激子在晶体表面的离域程度等对量子点激发电位及电子/空穴传输效率的影响，揭示量子点NECL的基本规律。在此基础上，通过均相反应、磁性富集、双亲性硅载体等策略构建智能化NECL传感界面,系统研究发光单元强度、水平发光界面大小及垂直界面组装效率等因素对NECL成像信号的影响。以猪传染性疾病标志物为模型，建立量子点NECL成像的可视化诊断平台，实现对复杂样品的高灵敏、原位分析，为动物疾病的现场诊断提供重要的方法学参考。

近红外量子点是一类全新的电化学发光试剂，近红外光具有组织穿透性好、背景干扰低、光化学损伤小等优点，展现出重要的分析应用前景。本项目在近红外量子点合成、电化学发光机理、检测应用及成像方面开展了研究工作，研究进展包括如下几方面：. 一、以微波辐照法和两亲胶束辅助相转移法合成了成分可调、尺寸可控（5-20纳米）、量子产率高的CdTe/CdS和CuInS2/ZnS电致化学发光试剂合成方法。利用电活性微生物还原法制备了具有高效电催化活性金钯合金纳米粒子，应用原子缺位调控策略，实现了钯纳米材料电催化性能的增强。. 二、结合电化学、光谱学方法阐明近红外CdTe/CdS量子点为共反应剂辅助的阴极带隙电化学发光机制。. 三、利用适配体、抗体对目标分子的高度特异性识别能力，基于主客体识别、纳米微粒负载大量信号标签等技术，发展了一系列传感检测技术，构建了高性能信号放大电化学发光传感器，实现了对动物疫病的高灵敏检测。利用比率型检测抗检测环境干扰的性质，构建了比率型电化学发光及比率型电化学-电化学发光传感界面，实现了对疾病标志物凝血酶、生物毒素的检测。. 四、以Leica显微镜为平台，搭建了显微电化学发光成像平台。. 本项目还拓展了工作内容，发现了功能化多壁碳纳米管促进根瘤菌-豆科共生固氮系统中结瘤和固氮酶活性效应；制备了自组装嵌合肽纳米粒子探针，利用肿瘤微环境与正常组织的差异，实现了纳米探针的靶向富集及药物的可控释放，在肿瘤成像诊断及光动力学治疗研究中取得系列进展。. 在项目资助下共计发表包括Adv. Mater.、ACS Nano在内的55篇论文，其中影响因子5.0以上论文42篇，影响因子10.0以上论文4篇，申请专利1项。相关论文被 Chem. Rev.、Chem. Soc. Rev.、JACS、Small、Anal. Chem. 等权威杂志引用300余次。共参加国内外学术交流会议9次，培养博士毕业生7名，硕士毕业生8名。.