巯基丁二酸修饰的碲化镉量子点溶液显现不同客体表面潜指纹

利用具有宽且连续的荧光激发光谱和窄且对称的荧光发射光谱的水溶性巯基丁二酸修饰的碲化镉量子点溶液,成功显现了多种客体表面的潜指纹,且1～3s即可得到良好效果.该材料成功显现了水浸客体和粘连客体表面的潜指纹,而且在显现连续按捺产生的微弱指纹时展现出了优良的灵敏度.同龙胆紫、罗丹明6G和巯基乙酸修饰的CdTe量子点溶液相比,该溶液拥有更快的显现速度和更好的显现效果.     

量子点的制备及应用研究进展

综述了量子点的制备方法以及在分析检测、生物、药学、光电器材、指纹显现等领域的应用.指出量子点是一种新型的荧光纳米材料,因其具有独特的光电性质而引起了广泛的关注;并就它的发展方向及应用前景进行了展望.     

量子点在法庭科学手印显现中的研究进展

随着纳米技术的进步,纳米颗粒正在被逐步应用到法庭科学领域的手印检验之中。近年来,半导体量子点因其良好的荧光特性而备受国内外法庭科学家的推崇,但大多数半导体量子点具有毒性,且会对环境造成污染,这些问题制约了半导体量子点在法庭科学领域中的应用。与传统有机染料和金属内核的半导体量子点相比,碳量子点具有毒性低、污染小、生物相容性优异的特点,现已应用于医学、生物、化学等多个领域。本文综述了半导体量子点在手印显现中的应用,介绍了碳量子点的研究进展,并指出碳量子点显现手印是今后法庭科学领域的重要研究方向。     

茚三酮在潜指纹显现与增强中的原理与应用

茚三酮最初用于分析化学和生物化学中的氨基酸检测,后来被引入法庭科学领域,成为显现纸张等渗透性客体上潜指纹的最常用的试剂,具有很高的显现灵敏度。介绍了茚三酮的发现与应用历史,与氨基酸的反应过程,以及其在潜指纹显现与增强中的应用,从而可以将法庭科学的技术和原理拓展至有机化学、配位化学的教学内容。     

CdTe/CdSe核壳量子点的合成及其在指纹显现中的应用

以CdCl2和Te粉为原料,在水相中合成了CdTe量子点核;通过外延生长在CdTe量子点核上包覆一层CdSe量子点,得到具有良好荧光性能的CdTe/CdSe核壳量子点;采用X射线衍射仪、透射电镜、高分辨透射电镜分析了不同反应条件下合成的CdTe/CdSe核壳量子点的晶体结构和微观结构,并对其进行了荧光光谱等测试和指纹显现分析.结果表明,合成的CdTe和CdTe/CdSe量子点粒径在3～5nm之间,粒径分布窄,水分散性良好;可以通过控制反应时间和Te/Se比等得到在500～700nm显示荧光发射峰的CdTe/CdSe核壳量子点.此外,核壳CdTe/CdSe量子点可以有效地和指纹物质结合,可应用于对铝合金油潜指纹的鉴别.     

Ⅰ-Ⅲ-Ⅵ族量子点的制备及其在照明显示领域的应用

半导体量子点因其独特的光电性质, 在发光二极管、太阳能电池和生物标记等领域展现出广阔的应用前景。传统的Ⅱ-Ⅵ和Ⅲ-Ⅴ族二元量子点具有优异的发光性能, 但其所含的Cd、Pb等有毒重金属元素极大制约了大规模商业应用。Ⅰ-Ⅲ-Ⅵ 族多元量子点作为近年来兴起的一类新型荧光材料, 其具有无毒、带隙可调、Stokes位移大、荧光寿命长等特性, 被认为是替代传统二元量子点的理想材料, 因此成为了科研工作者研究的热点。本文详细介绍了Ⅰ-Ⅲ-Ⅵ 族量子点的研究进展, 从该类量子点的基本性质出发阐明其光学性能的调控机制, 重点介绍了近年来该类量子点的有机相及水相制备技术, 对其在照明显示领域应用的研究进展进行了总结, 并与其他类型量子点器件的最新研究现状进行了对比。最后, 分析了Ⅰ-Ⅲ-Ⅵ 族量子点发展过程中有待解决的主要问题, 并对其今后的发展方向进行了展望。     

水溶性InP/ZnS量子点的合成及其在指纹显现中的应用

以磷化锌、氯化铟为原料,以十二烷胺为溶剂,在150～200℃下合成了InP量子点,通过相转移和紫外光照得到了巯基乙酸修饰的水溶性InP/ZnS量子点.利用X射线衍射仪、透射电镜、高分辨透射电镜、荧光光谱仪等分析了不同温度下合成的量子点的粒径、形貌、荧光性能及指纹显现效果.结果表明,合成的InP和InP/ZnS量子点为球...     

碳基量子点荧光传感器在环境检测中的应用研究

由于碳基量子点优越的光学性能、良好的水溶性及良好的生物相容性，其在荧光传感器方面的应用引起了越来越多人的关注，特别是其对金属离子卓越的检测性能使其广泛应用于环境检测。为了更好的了解到碳基量子点的应用，从碳量子点、石墨烯量子点、氧化石墨烯量子点的合成和近十年来关于其在环境检测中的应用做了总结，并对碳基量子点荧光传感器的应用做了展望。     

功能化量子点应用于无机离子和小分子识别

量子点作为新型荧光材料广泛应用分子识别研究,其表面功能化修饰能有效改善它在分子识别中的选择性和灵敏度。本文按功能化基团与量子点的连接方式分类,分为：以硫原子为连接基的功能化量子点（包括简单巯基化合物修饰的量子点、以简单巯基化合物为前驱体修饰的量子点、其他类型含巯基化合物修饰的量子点以及含-CS2化合物修饰的量子点）、以氧原子为连接基的功能化量子点和以氮原子为连接基的功能化量子点。评述了近5年来以上述类别的功能化量子点在无机离子和小分子识别研究中的应用。     

荧光可视化技术在食品分析中的应用进展

介绍了常见的荧光可视化传感器(比率、纸基、分子印迹荧光传感器),荧光可视化传感机制(荧光共振能量转移、内滤效应、光诱导电子转移、聚集诱导猝灭、聚集性诱导发射、分子内电荷转移、金属-配体电荷转移等)及其判定方法，综述了量子点(普通量子点和生物质量子点)、有机荧光物质和金属荧光纳米团簇等发光物质作为荧光可视化探针在食品分析中的应用，并对其发展前景进行了展望(引用文献69篇)。     

Fluorescent quantum dots for microbial imaging

QDs (Semiconductor QDs, CDs, SiQDs, and Pdots) are used in imaging microorganisms including viruses, bacteria, and fungi.     

Highly fluorescent streptavidin-coated CdSe nanoparticles: preparation in water, characterization, and micropatterning

CdSe quantum dots (QDs) with a high fluorescence quantum yield of 25% and a narrow size distribution were synthesized in a single step in water using glutathione as a stabilizing molecule. The exceptional optical properties enabled for the first time the detection of in-water-prepared single quantum dots at room temperature. For application as fluorescent bioanalytical probes, the QDs were coated with streptavidin. These QDs self-assemble with high contrast on micropatterned biotin while preserving their optical properties and their capability to bind in addition biotinylated molecules, a prerequisite for the development of novel supramolecular structures and bioassays.     

Current Advances in Quantum‐Dots‐Based Photoelectrochemical Immunoassays

As a newly developed technique, photoelectrochemical (PEC) immunoassays have attracted great attention in recent years because of their low cost and desirable sensitivity. Because the detection signal originates from the photoelectric conversion of photoelectric materials, the appearance and application of quantum dots (QDs), which possess unique photophysical properties and regulated optoelectronic characteristics, has taken the development of PEC immunoassays to new heights. This review concisely introduces the general mechanism of QDs‐based photoelectric conversion for immunoassays and summarizes the current advances in QD applications in immunoassays. Given that signal strategies and photoactive materials are the key elements in PEC biosensor systems, we comprehensively highlight the state‐of‐the‐art signaling strategies and various applications of QDs in PEC immunoassays to introduce advances in QDs‐based PEC immunoassays. Finally, challenges and future developmental trends are briefly discussed     

Microstructure-controlled aerosol-gel synthesis of ZnO quantum dots dispersed in SiO2 nanospheres

ZnO quantum dots dispersed in a silica matrix were synthesized from a TEOS:Zn(NO(3))(2) solution by a one-step aerosol-gel method. It was demonstrated that the molar concentration ratio of Zn to Si (Zn/Si) in the aqueous solution was an efficient parameter with which to control the size, the degree of agglomeration, and the microstructure of ZnO quantum dots (QDs) in the SiO(2) matrix. When Zn/Si ≤ 0.5, unaggregated quantum dots as small as 2 nm were distributed preferentially inside SiO(2) spheres. When Zn/Si ≥ 1.0, however, ZnO QDs of ～7 nm were agglomerated and reached the SiO(2) surface. When decreasing the ratio of the Zn/Si, a blue shift in the band gap of ZnO was observed from the UV/Visible absorption spectra, representing the quantum size effect. The photoluminescence emission spectra at room temperature denoted two wide peaks of deep-level defect-related emissions at 2.2-2.8 eV. When decreasing Zn/Si, the first peak at ～2.3 eV was blue-shifted in keeping with the decrease in the size of the QDs. Interestingly, the second visible peak at 2.8 eV disappeared in the surface-exposed ZnO QDs when Zn/Si ≥ 1.0.     

基于Mn掺杂ZnS量子点的室温磷光传感应用的研究进展

与一般有机染料分子相比,半导体材料量子点具有优异的光学性能,在多个领域得到了广泛的应用.量子点具有窄而对称且可调的发射波长、宽激发强吸收、抗光漂白能力强以及水溶性好等诸多优势,引起了研究者广泛关注.为了增加量子点的斯托克斯位移从而很好地避免量子点的自猝灭现象,引入掺杂物是一种很有效的方式.掺杂量子点不仅保留了量子点原有的优点,而且还赋予量子点额外的优异性能.如Mn掺杂ZnS量子点生物相容性好,不含Cd和Hg等有害元素,而且Mn2+的加入使其具有优异的室温磷光特性.磷光检测能很好地避开生物背景荧光的干扰,使得Mn掺杂ZnS量子点能够广泛应用于磷光生物分析.本文综述了Mn掺杂ZnS量子点在室温磷光分析中的研究进展,着重介绍了几种具有启发意义的设计策略,包括其发光机理以及应用于离子、分子以及生物大分子等的检测.     

油胺/油酸稳定的CdSe量子点的绿色合成

以液体石蜡为高温反应溶剂,油酸和油胺为混合稳定剂,利用高温热解法一步合成了高质量的CdSe量子点。通过紫外-可见吸收光谱、荧光发射光谱、红外光谱和X射线衍射等手段对量子点的光学性质和结构进行了表征。结果表明,油胺/油酸混合表面活性剂稳定的量子点吸收光谱峰形更尖锐,荧光发射光谱半峰宽更窄。反应温度和反应时间均对量子点的生长过程和光学性质有明显影响,220℃下反应15 min,荧光量子产率可达26%。得到的CdSe量子点为立方晶型,表面同时包覆了油酸和油胺,具有良好的光稳定性。该方法无需使用三烷基膦,价廉环保,且合成的CdSe量子点性质稳定、性能优越,有利于其在分析检测领域中的应用。     

Cell-penetrating quantum dots based on multivalent and endosome-disrupting surface coatings

We report the development of cell-penetrating quantum dots (QDs) based on the use of multivalent and endosome-disrupting (endosomolytic) surface coatings. Hyperbranched copolymer ligands such as polyethylene glycol (PEG) grafted polyethylenimine (PEI-g-PEG) are found to encapsulate and solubilize luminescent quantum dots through direct ligand-exchange reactions. Because of the positive charges and a "proton sponge effect" associated with multivalent amine groups, this class of ligand-exchanged QDs is able to penetrate cell membranes and is also able to disrupt endosomal organelles in living cells. The grafted PEG segment is essential for reducing the cytotoxicity of PEI as well as for improving the overall nanoparticle stability and biocompatibility. In comparison with previous QDs encapsulated with amphiphilic polymers, the cell-penetrating QDs are smaller in size and are considerably more stable in acidic environments. Cellular uptake and imaging studies reveal that the number of PEG grafts per PEI molecule has a pronounced effect on the intracellular pathways of internalized QDs. In particular, QDs coated with PEI-g-PEG2 are rapidly internalized by endocytosis, and are initially stored in vesicles, followed by slow endosomal escape and release into the cytoplasm. These insights are important toward the design and development of nanoparticle agents for intracellular imaging and therapeutic applications.     

One- and two-photon induced polymerization of methylmethacrylate using colloidal CdS semiconductor quantum dots

The development of one- and two-photon induced polymerization using CdS semiconductor quantum dots (QDs) and amine co-initiators to promote radical generation and subsequent polymerization is presented. Two-photon absorption (TPA) cross-section measurements, linear absorption, and transmission electron microscopy are used to characterize the QDs. The effectiveness of the co-initiators in increasing the efficiency of photopolymerization (polymer chains formed per excitation) is examined. Triethylamine was observed to be most effective, yielding quantum efficiencies of initiation of >5%. The interactions between the co-initiators and QDs are investigated with steady-state photoluminescence and infrared spectroscopies. Possible initiation mechanisms are discussed and supported by electrochemical data. Making use of the surface chemistry developed here and the large QD TPA cross-sections, two-photon induced polymerization is demonstrated. The large TPA cross-sections coupled with modest quantum efficiencies for initiation reveal the unique potential of molecularly passivated QDs as efficient two-photon photosensitizers for polymerization.     

Recent advances and applications in QDs-based sensors

As a unique nanomaterial, quantum dots (QDs) are not only applied in fluorescent labeling and biological imaging, but are also utilized in novel sensing systems. Because QDs have attractive optoelectronic characteristics, QD-based sensors present high sensitivity in detecting specific analytes in the chemical and biochemical fields. In this review, we describe the basic principles and different conjugation strategies in QD-based sensors. An overview of recent advances and various models of QD-sensing systems is also provided. Furthermore, perspectives for sensors based on QDs are discussed.     

Advances in green colloidal synthesis of metal selenide and telluride quantum dots

This review summarized the green approaches toward colloidal chemical synthesis for metal selenide and telluride quantum dots.