量子点阳极近红外电致化学发光及其传感平台的构建

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 improve and enrich the quantum dot-based anode near-infrared electrogenerated chemiluminescence (NECL) theories, and to develop quantum dot-based anode NECL sensors. To develop new strategies for the aqueous synthesis of near-infrared quantum dots, series of high-quality water-soluble near-infrared quantum dots are prepared by surface state regulation, band alignment tunableness or ingredients doping methods. The relationship between the structure types and surface states of quantum dots together with their excitation potential are systematically investigated. The effects of high lattice-mismatch core-shell and gradient core-shell type I quantum dots on the main anode NECL models are deeply discussed. The basic reasons of band gap NECL from mononuclear quantum dot with some defects are revealed in detail. On this basis, the effects of electron transfer conditions on NECL both intensity and stability are also systematically studied, and the band gap anode NECL reagents with low potential, strong intensity and high stability are selected. Different kinds of reliable and efficient anode NECL sensing platforms based on quantum dots are created by using nanomaterials and biotechnology for signal amplification, and small molecule, protein and DNA as models, which can not only be used for highly sensitive detection of complex biological samples, but also provide a scientific evaluation and an important way for interfere-free near infrared analysis and quantum dot-based anode NECL sensing, respectively.

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。本项目以完善量子点阳极近红外电致化学发光（NECL）理论体系，发展阳极NECL传感技术为目标，在制备表面态可控、带隙能级可调及成分掺杂等系列高质量水溶性近红外量子点的基础上；系统研究量子点阳极NECL激发电位与量子点结构类型和表面态的关系；深入探讨高晶格错配核壳/梯度核壳I型量子点对阳极NECL发光形式的影响，揭示单核缺陷量子点带隙NECL的基本原因。系统研究电子转移条件对阳极NECL发光强度及其稳定性的影响，筛选低电位、强发光、高稳定的带隙阳极NECL试剂；借助纳米材料和生物放大技术，以小分子、蛋白质、DNA等为分析模型，发展实用、高效及多样化的阳极NECL传感平台，实现对复杂生物样本的直接高灵敏检测，为近红外无干扰分析作出科学评估和量子点阳极NECL传感提供重要的方法学参考。

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。虽然量子点 ECL 传感技术作为一种强大的分析工具已经广泛用于化学与生命科学领域，但是随着对复杂多细胞生物体研究的不断深入，传统 ECL 探针也面临巨大挑战。量子点近红外电致化学发光（NECL）研究已经出现并且越来越受到国内外同行的关注。本项目以完善量子点近红外电致化学发光（NECL）理论体系，发展阳极NECL传感技术为目标，在制备表面态可控、带隙能级可调的CdTe/CdSe和CdTe/CdS高质量水溶性近红外量子点基础上，系统研究了量子点阳极激发电位与量子点表面态及核壳结构的关系；实验表明在ITO电极表面CdTe/CdS量子点在+1.32 V时有稳定强烈的NECL信号。深入探讨了II型核壳与I型核壳量子点对阳极NECL发光形式的影响，实验发现I型ZnS及CdS壳层能够有效钝化量子点表面，揭示了CdTe/CdS小核厚壳量子点带隙NECL的基本原因。系统研究电解质、pH、扫描速率、电极材料等对NECL发光强度及其稳定性的影响，获得了低电位、强发光、高稳定的CdTe/CdS NECL试剂，在此基础上，发展了量子点阳极NECL高灵敏检测湖水和牛奶中Cu2+的新方法，检测限可达20 nmol；另外，借助金纳米棒和共振能量转移技术，以凝血酶为分析模型，实现对复杂生物样本的直接超灵敏分析，检测限达20 amol，为近红外无干扰分析作出科学评估和量子点阳极NECL传感提供重要的方法学参考。