荧蒽修饰的四苯基乙烯衍生物:分子合成、聚集增强荧光特性及其对苦味酸的高灵敏度检测

由于聚集体和固态发光量子效率高等优点,因此聚集诱导发光（AIE）材料成为光电功能材料研究领域的热点,拓展AIE分子体系始终是这一领域中的关键和基础的科学问题.通过Suzuki-Miyaura偶联这一条件较为温和的反应,将AIE生色团四苯基乙烯（TPE）与荧蒽直接共轭键接,制备得到单荧蒽和双荧蒽修饰的TPE衍生物TPE-FA与TPE-DFA,它们具有聚集增强荧光（AEE）行为,聚集体发射峰值波长分别在477和494 nm,固体薄膜的绝对荧光量子产率高达74.1%和40.4%.它们可以高灵敏地检测苦味酸,荧光猝灭常数大,检出限低于1 μg·g^-1.这两种AEE分子可望用于其它多硝基取代的芳香类吸电子分子的检测.     

聚集诱导发光机理研究

与传统荧光生色团聚集后导致荧光猝灭相反,有一类化合物在单分子状态下荧光微弱甚至观察不到荧光,而在聚集状态下荧光显著增强,这就是聚集诱导发光(AIE)现象。AIE现象独特的优越性使得众多研究组开发出越来越多的新AIE体系,其机理也被广泛而深入地研究。本文总结了目前为止已经提出的AIE机理,包括分子内旋转受限、分子内共平面、抑制光物理过程或光化学反应、非紧密堆积、形成J-聚集体以及形成特殊激基缔合物等;着重评述了目前研究最为全面、适用范围最广的分子内旋转受限机理。同时介绍了一些基于这些机理设计的新AIE体系。     

荧光共轭聚合物在生物大分子检测中的应用*

共轭聚合物因其具有π-电子体系及共轭离域结构,一般都具有优异的发光性能,其发光强度和发射波长会随被检测化合物结构的不同而发生特异性响应,特别是在与被检测物相互作用过程中所产生电荷和能量能够沿共轭分子链进行有效传递,成倍放大这种作用,从而有效提高了检测灵敏度,这比相应的小分子化合物更具有优越性。目前共轭聚合物已被用于开发新型化学、生物传感器,尤其是在生物分子检测方面的应用得到迅速的发展。本文总结了近年来荧光共轭聚合物在生物传感方面的研究进展,主要讨论共轭聚合物在蛋白质、核酸及毒素检测中的应用。     

Aggregation-Induced Emission: Recent Advances in Materials and Biomedical Applications

The concept of aggregation-induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image-guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field.     

α-吡喃酮衍生物的合成及聚集荧光增强性质研究

设计合成了具有4个苯基取代的α-吡喃酮衍生物,研究了该化合物在溶液中的稳态光物理过程,以及在四氢呋喃/水混合溶剂中的聚集行为和发光性质.该化合物在良溶剂中几乎没有发光,而形成聚集体后发出明亮的蓝绿色荧光,荧光量子产率达17%,比溶液中增强了253倍.根据化合物的结构和低温荧光实验结果推断,聚集荧光增强主要是聚集体中分子...     

Aggregation‐Induced Emission: Recent Advances in Materials and Biomedical Applications

The concept of aggregation‐induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image‐guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field.     

4,4'-[(2,2-二苯乙烯)-1,1-双(4,1-亚苯基)]二吡啶的合成、表征及其聚集诱导发光性能研究

以提升学生的实验操作及创新能力为目的的综合化学实验，采用简单的2步法（缩合和Suzuki反应）合成了一种具有聚集诱导发光性能的化合物4，4'-[（2，2-二苯乙烯）-1，1-双（4，1-亚苯基）]二吡啶（简称2Py-TPE）。利用过滤、洗涤、萃取、干燥和柱层析等常用的有机分离操作手段对该化合物进行纯化；使用核磁共振仪、高分辨质谱仪、红外光谱仪及稳态瞬态荧光光谱仪对其进行结构表征和聚集诱导发光性能研究。该实验不仅可以促使学生了解以四苯乙烯衍生物为代表的聚集诱导发光材料的研究现状，而且能够培养学生的综合实验能力和科学探究能力。     

New tetraphenylpyridinium-baseci luminogens with aggregation-induced emission characteristics

The research on aggregation-induced emission （AIE） has drawn increasing interests in the past decade. With the efforts scientists paid, a variety of AIE systems have been developed, among which the tetraphenylethelene and silole derivatives are the most studied. Development of new AIE systems could further enrich the AIE molecules and promote the development of AIE area. In this communication, we prepared a new AIE system based on 1,2,4,6-tetraphenylpyridinium ions according to the restriction of intramolecular rotation mechanism. These molecules could be facilely synthesized via one-step and one-pot reaction. The ionic AIE-active molecules could find wide application in sensing and optoelectronic areas.     

Asymmetric Catalytic Assembly of Triple-Columned and Multilayered Chiral Folding Polymers Showing Aggregation-Induced Emission (AIE)

Unprecedented chiral multilayer folding 3D polymers have been assembled and regulated by uniform and differentiated aromatic chromophore units between naphthyl piers. Screening catalysts, catalytic systems and monomers were proven to be crucial for asymmetric catalytic Suzuki–Miyaura polycouplings for this assembly. X-ray crystallography of the corresponding dimers and trimers revealed the absolute configuration and the intermolecular packing pattern. Up to 61 960 M_w/41 900 M_n and m/z 4317 for polymers and oligomers, as confirmed by gel permeation chromatography (GPC) and MALDI-TOF MS, indicated that these frameworks were composed of multiple stacked layers. The resulting multiple π-assemblies exhibited remarkable optical properties in aggregated states (photoluminescence in solids and aggregation-induced emission in solutions), as well as reversible redox properties in electrochemical performance.     

水溶性含糖共轭聚合物的制备及应用

水溶性共轭聚合物具有优异的光学稳定性、高亮度、易于修饰和水溶性等特点,广泛应用于离子检测、蛋白检测和生物成像等领域。水溶性共轭聚合物主要通过在共轭聚合物的侧基或端基修饰水溶性的离子基团或水溶性聚合物实现其水溶性,水溶性共轭聚合物还可以通过引入功能性基团或聚合物使其具备不同的功能特性。糖化合物是天然存在的一类生物分子且大部分具有水溶性的特点,因此最近十几年来科研工作者将糖化合物引入共轭聚合物中以赋予共轭聚合物糖化合物的生物功能特性。本文总结了水溶性含糖共轭聚合物的制备方法、化学结构及其在凝集素、细菌检测和细胞荧光成像中的应用。最后总结了此类聚合物的特性、发展方向及目前所需解决的问题。     

含磷酰杂菲苯甲酸对苯二酯的聚集诱导发光增强性能及其在检测过渡金属离子中的应用

有机化合物因成膜以后荧光淬灭而使其应用受到很大限制, 所以研究、开发能在聚集状态下呈现优异发光性能的新材料就尤为重要. 由于分子间π-π和极性共同相互作用, 使得磷酰杂菲环的转动受到限制, 从而使苯甲酸-2-[6-氧化-6-氢-二苯基(c,e)＜1,2＞氧杂磷酰基]-1,4-二羟基苯二酯(OP)在达到一定规整聚集程度时, 荧光强度成倍增加, 具有了聚集诱导发光增强(AIEE)性质. 实验结果表明: 浓度低于1×10^－6 mol•L^－1 的OP会失去AIEE性质; 浓度为1×10^－4 mol•L^－1的Hg^2＋, Fe^2＋和 Fe^3＋会分别淬灭浓度为1×10^－5 mol•L^－1 OP荧光强度的26%, 34%, 74%, 而Pb^2＋, Zn^2＋, Cd^2＋, Co^2＋, Mn^2＋, Cu^2＋, Ni^2＋, Ag^＋等离子的淬灭效率却很低, 这一性质表明该化合物可以用作过渡金属离子的特异性检测材料.     

Synthesis of Water‐Soluble Dendritic Conjugated Polymers for Fluorescent DNA Assays

Summary: Cationic water‐soluble dendritic poly(fluorene)s with positively charged amines on the exterior (PFP‐G_0–2) can be prepared by a macromonomer (generation‐by‐generation) approach. The charge densities of PFP‐G_0–2 can control their distances to DNA by electrostatic interactions. The PFP‐G₂ with higher generation of dendritic side chains possesses a higher charge density, and gives rise to efficient fluorescence resonance energy transfer (FRET) to a signaling fluorescein labeled at the terminus of DNA. These new conjugated polymers form less aggregates and yield more efficient FRET in a tetrahydrofuran/H₂O mixed solvent as compared to in pure water. The sensitivity of the DNA sensor is improved by utilizing highly dendritic conjugated polymers.

Structure of the dendritic conjugated polymer PFP‐G₂.     

共轭微孔聚合物的制备与应用

共轭微孔聚合物(CMPs)是一类有机多孔聚合物,与常规共轭聚合物或多孔材料相比,其最大的特点是既有π共轭骨架又具有大量微孔.这类材料在解决能源和环境问题方面显示出巨大的潜力,已在气体吸附、非均相催化、发光材料、化学传感器、电能存储和生物杂化物等领域显示出巨大的应用前景.目前已开发出多种用于CMPs结构单元设计与合成的新...     

Alkene Metathesis – A Tool for the Synthesis of Conjugated Polymers

Alkene metathesis is a superb methodology. We report the progress using alkene metathesis in the synthesis of polymeric organic semiconductors. Three classes of polymers have been synthesized using acyclic diene metathesis (ADMET) or ring opening metathesis polymerization (ROMP), viz., poly(acetylene)s (PA), poly(arylene‐vinylene)s (PAV), and organometallic polymers. For PAs, ROMP of cyclooctatetraenes is best, whereas for PAV, both ADMET and indirect and direct ROMP are viable. Metathesis performs flawlessly with the correct monomers, as molybdenum and particularly the robust Ru carbenes demonstrate. When performing ROMP, one is often rewarded with structurally uniform polymers that can display very low polydispersities. Overall, metathesis is a powerful tool for the preparation of semiconducting polymers.     

An AIE‐Active Conjugated Polymer with High ROS‐Generation Ability and Biocompatibility for Efficient Photodynamic Therapy of Bacterial Infections

New, biocompatible materials with favorable antibacterial activity are highly desirable. In this work, we develop a unique conjugated polymer featuring aggregation‐induced emission (AIE) for reliable bacterial eradication. Thanks to the AIE and donor‐π‐acceptor structure, this polymer shows a high reactive oxygen species (ROS)‐generation ability compared to a low‐mass model compound and the common photosensitizer Chlorin E6. Moreover, the selective binding of pathogenic microorganisms over mammalian cells was found, demonstrating its biocompatibility. The effective growth inhibition of bacteria upon polymer treatment under light irradiation was validated in vitro and in vivo. Notably, the recovery from infection after treatment with our polymer is faster than that with cefalotin. Thus, this polymer holds great promise in fighting against bacteria‐related infections in practical applications.     

Alkyne‐Linked Poly(1,8‐carbazole)s: A Novel Class of Conjugated Carbazole Polymers

Novel conjugated carbazole polymers based on the alkyne‐linked 1,8‐carbazole structure are synthesized in high yield by the Sonogashira cross‐coupling reaction and acetylenic oxidative coupling reaction. The polymers are thermally stable and highly soluble in common organic solvents such as CHCl₃, CH₂Cl₂, and THF. As compared to ethynylene‐linked polymer, the butadiynylene‐linked polymer display a bathochromic shift in the absorption maximum and end absorption position. In addition, the fluorescence behaviors in CH₂Cl₂ are almost identical for both polymers. Electrochemical measurements indicate that the ethynylene‐linked polymer possesses a lower first oxidation potential than the butadiynylene‐linked one.

     

水溶性共轭聚电解质

水溶性共轭聚电解质主要是指含离子型官能团侧链的共轭聚合物,可在水或其它极性有机溶剂中能够溶解。这类化合物把传统共轭聚合物的光电性质和聚电解质的水溶性特点结合在一起,显示出的一些独特性质,可在新一代光电器件制作和化学生物荧光传感器中获得多样的应用。本文总结了近10年来报道的水溶性共轭聚电解质的结构特点和合成方法,以及对不同化学或物理条件下光物理性质的研究,归纳了它们在新一代光电器件制作和荧光传感中的应用,并在此基础上提出了水溶性共轭聚电解质研究中尚待解决的问题,并展望了水溶性共轭聚电解质的应用前景。     

A Conjugated Polymeric Supramolecular Network with Aggregation‐Induced Emission Enhancement: An Efficient Light‐Harvesting System with an Ultrahigh Antenna Effect

Superior artificial light‐harvesting systems (ALHSs) require exceptional capacity in harvesting light and transferring energy. In this work, we report a novel strategy to build ALHSs with an unprecedented antenna effect (35.9 in solution and 90.4 in solid film). The ALHSs made use of a conjugated polymeric supramolecular network (CPSN), a crosslinked network obtained from the self‐assembly of a pillar[5]arene‐based conjugated polymeric host ( CPH ) and conjugated ditopic guests (Gs). The excellent performance of the CPSN could be attributed to the following factors: 1) The “molecular wire effect” of the conjugated polymeric structure, 2) aggregation‐induced enhanced emission (AEE) moieties in the CPH backbone, and 3) high capacity of donor–acceptor energy transfer, and 4) crosslinked structures triggered by the host–guest binding between Gs and CPH . Moreover, the emission of the CPSN could be tuned by using different Gs or varying the host/guest ratio, thus reaching a 96 % sRGB area.     

Single Base Pair Mismatch Detection Using Cationic Conjugated Polymers through Fluorescence Resonance Energy Transfer

A simple method using water‐soluble conjugated polymers and a DNA intercalator has been proposed for single base pair mismatch detection with enhanced detection efficiency. Fluorescence resonance energy transfer (FRET) was used as an indicator for unwinding of dsDNA due to base pair mismatch at elevated temperatures. The optical amplification effect of the CPs helps to achieve enhanced detection efficiency.