枝状体系中分子内光诱导能量转移*

枝状分子因其独特的化学结构,其光化学与光物理研究尤为引人注目。本文重点介绍了近二十年来报道的具有光诱导分子内能量转移的枝状分子的化学结构特点,分析了不同因素对光诱导分子内能量转移效率的影响;阐述了可以根据能量给体与受体的性质,利用化学策略对枝状体的分子内光诱导能量转移进行调控;概括了具有光诱导分子内能量转移性质的枝状分子的目前应用领域;总结了枝状体中分子内能量转移面临的关键科学问题,并展望了具有分子内能量转移的枝状分子的发展方向     

超分子体系中的光物理和光化学过程

总结了我们组近几年来对超分子体系中的光物理和光化学过程所做的工作,包括三个部分：(1)微反应器控制的有机光化学反应的选择性,(2)疏水、疏脂作用对光物理和光化学过程的影响,(3)超分子体系中的电子转移、能量传递和光化学转换。     

铱配合物在磷光化学传感器中的应用

由于在生物领域和物联网领域的广泛应用,化学传感器在近期发展迅速.相比于纯有机分子的荧光化学传感器,基于重金属配合物的磷光化学传感器由于发光寿命长,斯托克斯位移大等优点越来越引起人们的广泛关注.重金属铱配合物三线态寿命短,发光效率高而且配合物的发射波长容易受配体的改变而发生变化,因此成为最好的磷光传感器材料之一.本文介绍了铱配合物在磷光化学传感器领域中的应用,具体包括:阳离子传感器、阴离子传感器、氧分子传感器、氨基酸传感器、pH传感器等,并指出了相比于其它磷光化学传感器,基于铱配合物的磷光化学传感器的优势以及目前所存在的问题,最后,对基于铱配合物的磷光化学传感器的研究和发展方向进行了展望.     

新型有机荧光探针分子的设计合成及在生物医学中的应用

近年来,荧光化学传感器以其高选择性、高灵敏度、实时原位监测、简便快捷等优点,受到人们的普遍欢迎.开发一些具有高灵敏度、高选择性、实时原位检测性能的荧光化学传感器,特别是开发一些具有实际应用价值的荧光化学传感器,一直都是人们追求的目标.论文根据分子识别和光化学传感的基本原理,结合生物医学检测的需要,设计了几种能够在水相中识别生物医学上重要生物活性分子的荧光探针分子.主要工作和结果概述如下.     

以苝二酰亚胺为构筑块的超分子聚集体的研究进展

苝二酰亚胺(PDI)超分子聚集体以其独特的光物理和光化学性质而受到广泛的关注.本文首先简单介绍了苝二酰亚胺的性质及合成,然后分别介绍了在配位键、π-π堆积、氢键以及正负离子的静电引力作用下组装超分子聚集体的研究现状.最后对苝二酰亚胺超分子聚集体的发展前景作了展望.     

纳米比色化学传感器的设计及其在生物分子检测中的应用

<正>近年来,人们一直致力于制作能够在复杂实际样品中高灵敏度和选择性地检测被测物种的比色型光化学传感器.具备高选择性和灵敏度的比色型传感器的研究已经成为目前传感器领域的研究热点.纳米科技爆炸式的发展为优化比色型化学传感器的性能提供了可能.本论文基于对比色型光化学传感器的充分认识,和对纳米材料在构建比色型传感器     

功能分子体系的设计与构建

功能分子在外界刺激(酸、碱、光等)的诱导下能发生分子构型、构象变化,并引起相应的物理化学性质变化,或能实现特定的功能,例如具有方向性的电子、能量转移,对分子/离子的识别能力的调控,以及光/电开关功能.功能分子的设计是分子材料科学研究的基础.作者将就我们在分子机器,化学传感器等功能分子的设计合成与性质研究领域取得的进展作一总结,并对未来的发展进行了描述.     

Oxonol 染料的稳态光物理行为研究

对oxonol——一种带负电荷类菁染料化合物溶液的光谱和光物理问题进行了研究.发现它和一般分子内共轭的电荷转移化合物相比，无论在吸收光谱或荧光发射光谱上，都表现出不同的光物理和光化学行为.对出现的这种差异，特别是负的溶致变色行为和在不同pH条件下分子的互变异构等对吸收光谱的影响进行了讨论.     

反应型化学传感器的研究进展

反应型化学传感对目标分子的检测具有高度选择性和灵敏度,在环境监测和生命科学领域有着广泛的应用前景.综述了近几年来国内外检测阴、阳离子和中性分子的反应型传感器最新研究进展,并介绍了各种传感器的设计机理及其检测结果.     

反应型汞离子光化学传感器*

化学传感器提供了方便、快捷、廉价的分析检测有毒重金属离子的方法,具有很高的灵敏度和选择性。检测对象专一的反应型光化学传感器受到越来越多的关注。本文综述了识别Hg²⁺的反应型光化学传感器的最新研究进展。按照化学反应类型来分类,包括汞促进脱硫和脱硫醇反应、汞促进硫脲衍生物脱硫化氢分子内成环反应、羟汞化及加汞化反应等。     

光纤化学传感器进展

本文介绍光纤化学传感器的基本理论及其应用的最新进展，着色分析了荧光光纤化学传感器的应用。引用文献８０篇。     

Cooperative ratiometric chemosensors: pinwheel receptors with an integrated fluorescence system

The synthesis and fluorescent properties of a second generation cooperative chemical sensor are described. The sensor has two interacting binding pockets for cooperative recognition of two analytes. Cooperative binding activates a ratiometric fluorescent response via formation of an excimer. Binding was characterized by NMR, absorption, and fluorescence spectroscopy. The advantages of separating the recognition elements from the fluorescent response elements are discussed.     

Cell surface-anchored fluorescent aptamer sensor enables imaging of chemical transmitter dynamics

A fluorescent aptamer sensor was applied to the analysis of extracellular chemical transmitter dynamics. We utilized a tocopherol-labeled aptamer, which allowed the direct anchoring of the fluorescent aptamer on the cell surface while retaining its performance as a fluorescent sensor. The fast-responsive fluorescent DNA aptamer sensor, which targets adenine compounds, was anchored on the surface of brain astrocytes. Fluorescence imaging of the aptamer-anchored astrocytes enabled the real-time monitoring of release of adenine compounds as a gliotransmitter, which was synchronized with calcium wave propagation in neighboring cells.     

Pt/TiO_2光催化降解甲苯

选择甲苯作为研究对象 ,探讨了在不同光源照射、不同光催化剂的作用下 ,气相甲苯的降解情况 .结果表明甲苯在紫外杀菌灯照射下有明显的光化学反应发生 .在光催化剂作用、黑光灯照射时 ,甲苯发生光催化氧化反应 ;并对催化剂在降解甲苯反应中的失活原因做了初步探讨     

Semisynthesis of fluorescent metabolite sensors on cell surfaces

Progress in understanding signal transduction and metabolic pathways is hampered by a shortage of suitable sensors for tracking metabolites, second messengers, and neurotransmitters in living cells. Here we introduce a class of rationally designed semisynthetic fluorescent sensor proteins, called Snifits, for measuring metabolite concentrations on the cell surface of mammalian cells. Functional Snifits are assembled on living cells through two selective chemical labeling reactions of a genetically encoded protein scaffold. Our best Snifit displayed fluorescence intensity ratio changes on living cells significantly higher than any previously reported cell-surface-targeted fluorescent sensor protein. This work establishes a generally applicable and rational strategy for the generation of cell-surface-targeted fluorescent sensor proteins for metabolites of interest.     

A multi-functional fluorescent sensor for Zn2+ and HSO4− based on a new diarylethene derivative

A new photochromic diarylethene derivative with a hydralazine unit was designed and synthesized. It was not only acted as a Zn²⁺ sensor with the fluorescent color change from dark blue to bright orange, but also acted as a fluorescent sensor for HSO₄^? with the fluorescent color change from dark blue to bright blue. Furthermore, the derivative also exhibits multi-addressable switching properties by the stimulations of lights and chemical reagents. Based on these characteristics, two combinational logic circuits were constructed with the emission intensity as the output signals, and the UV/vis lights, chemical species as the input signals.     

Photophysics of indole-2-carboxylic acid in an aqueous environment studied by fluorescence spectroscopy in combination with ab initio calculations

The photo-physics and -chemistry of indoles are known to be highly complex and strongly dependent on their precise molecular structure and environment. Combination of spectroscopic analysis with quantum chemical calculations should be a powerful tool to unravel precise excited state deactivation mechanisms. At the same time, combined studies are seldom and likely far from trivial. In this work we explore the feasibility of combining spectroscopic and quantum-chemical data into one consistent model. The molecule of choice is indole-2-carboxylic acid (ICA) in aqueous media. Excited state dynamics are determined by time-resolved fluorescence experiments, while excited state reaction pathways of ICA-H(2)O clusters are explored by ab initio calculations.     

Fluorescent sensor array in a microfluidic chip

Miniaturization and automation are highly important issues for the development of high-throughput processes. The area of micro total analysis systems (muTAS) is growing rapidly and the design of new schemes which are suitable for miniaturized analytical devices is of great importance. In this paper we report the immobilization of self-assembled monolayers (SAMs) with metal ion sensing properties, on the walls of glass microchannels. The parallel combinatorial synthesis of sensing SAMs in individually addressable microchannels towards the generation of optical sensor arrays and sensing chips has been developed. [figure: see text] The advantages of microfluidic devices, surface chemistry, parallel synthesis, and combinatorial approaches have been merged to integrate a fluorescent chemical sensor array in a microfluidic chip. Specifically, five different fluorescent self-assembled monolayers have been created on the internal walls of glass microchannels confined in a microfluidic chip.     

Ratiometric and highly selective fluorescent sensor for cadmium under physiological pH range: a new strategy to discriminate cadmium from zinc

In a neutral aqueous environment, a new ratiometric Cd2+ fluorescent sensor 1a can successfully discriminate Cd2+ from Zn2+ by undergoing two different internal charge transfer (ICT) processes, and the high selectivity of sensor 1a to Cd2+ over some other metals was also observed. Moreover, through structure derivation and a series of NMR studies, the unique role of the 2-picolyl group (the part in red in the abstract graphic) in the sensor 1a-Cd2+ complexation was disclosed.     

A Single‐Wavelength‐Emitting Ratiometric Probe Based on Phototriggered Fluorescence Switching of Graphene Quantum Dots

Ratiometric fluorescent probes are of great importance in research, because a built‐in correction for environmental effects can be provided to reduce background interference. However, the traditional ratiometric fluorescent probes require two luminescent materials with different emission bands. Herein a novel ratiometric probe based on a single‐wavelength‐emitting material is reported. The probe works by regulating the luminescent property of graphene quantum dots with UV illumination as activator. The ratiometric sensor shows high sensitivity and specificity for iron ions. Moreover, the ratiometric sensor was successfully employed to monitor ferritin levels in Sprague Dawley rats with chemical‐induced acute liver damage. The proposed single‐wavelength ratiometric fluorescent probe may greatly broaden the applicability of ratiometric sensors in diagnostic devices, medical applications, and analytical chemistry.