聚集诱导发光应用研究进展

传统的荧光化合物在聚集态时,会导致荧光猝灭;而聚集诱导发光(AIE)化合物在溶液中单分子状态时呈现弱的荧光,但当形成聚集态时发出强的荧光,这是由于分子内旋转受阻(RIR)和聚集形态的改变所致.综述了2008年以来聚集诱导发光最新应用研究进展,如用以检测离子、气体、有机小分子、爆炸物、蛋白、酶等化学/生物传感器;向传统的聚集引起猝灭化合物引入AIE单元,制备高效固态发光器件等;通过压力、热、溶剂蒸汽等调控聚集态,构建可逆的刺激性多重响应材料;发展与生物体具有良好兼容性的聚集体杂化纳米颗粒(如荧光硅纳米颗粒、聚合物胶束、电解质等),以用于生物体内成像、结构解析及检测等.     

聚集诱导发光超分子聚合物的光物理性能研究

将一种含具有聚集诱导发光性能(AIE)的四苯乙烯的2-脲基-4[1H]-嘧啶酮衍生物(TPE-bis UPy)在氯仿中通过四重氢键作用组装形成的超分子聚合物,再以十六烷基三甲基溴化铵(CTAB)为表面活性剂利用微乳法制备了基于超分子聚合物的纳米球.这种纳米球的形貌通过SEM进行了表征,具有规整的形貌与尺寸.相比在溶液里,该超分子聚合物纳米球的荧光显著增强.通过改变单体的浓度得到了3种不同粒径的超分子聚合物纳米球,DLS表征其粒径分别为46、66和91 nm.将这3种不同粒径的TPE-bis UPy超分子聚合物纳米小球与带负电的曙红(EY)进行组装,由于静电相互作用曙红吸附在纳米球表面,拉近了TPE-bis UPy和曙红之间的距离,使得在组装体内TPE-bis UPy可以有效地将激发能传递给曙红分子,该体系的发光颜色从蓝色荧光变为黄绿色荧光,其能量传递效率分别为62%、55%和39%,洗去表面活性剂CTAB后静电作用减弱,能量传递效率显著降低,分别为46%、36%和33%.研究表明,TPE-bis UPy超分子聚合物纳米小球与曙红的组装体系内,静电作用越强能量传递效率越高;超分子聚合物纳米球粒径越小,能量传递效率越高;并且通过这种组装可以调控体系的发光颜色,能量传递也可以通过体系的发光颜色变化观察到.     

PNDC-b-PNTPE自组装制备兼具结构色和荧光色的薄膜

设计合成了含有聚集诱导发光四苯乙烯基的大位阻单体四苯乙烯基降冰片烯(NTPE),通过NTPE与含有双癸烷基的树状单体对苯二甲酸癸烷苯酯基降冰片烯(NDC)的顺序开环易位聚合(ROMP)制备具有聚集诱导发光性质的大位阻树状嵌段聚合物(PNDC-b-PNTPE).利用薄膜自组装制备了兼具结构色和荧光色的一维光子晶体薄膜.结果表明,PNDC-b-PNTPE在四氢呋喃(THF)中随着溶剂的挥发而快速自组装成为蓝色的一维光子晶体薄膜,其最大反射波长(λ_max)为443 nm.一维光子晶体薄膜的横截面扫描电子显微镜照片表明,PNDC-bPNTPE组装为周期为133 nm的层状结构.荧光发射光谱分析结果表明,一维光子晶体薄膜在368 nm波长紫外光的激发下能够发射最大波长为425 nm的荧光.该兼具结构色和荧光色的薄膜在防伪和显示方面有潜在的应用前景.     

咔唑基四苯乙烯多功能发光材料的合成与性能

设计合成了一个以四苯乙烯为核心,四端连接长烷基链的咔唑基四苯乙烯衍生物(TPECz),该化合物具有典型的聚集诱导发光(AIE)特性.紫外光谱(UV-Vis)、荧光光谱(PL)、热重(TG)和示差扫描量热(DSC)研究表明,该化合物属于深蓝光材料、具有较好的热稳定性,并且对金属Fe3+具有很好的识别作用,有望用于金属离子检测;同时,该化合物外围的咔唑基团具有电化学活性,采用电化学聚合方法可制备其聚合物交联荧光薄膜,扫描电镜(SEM)和原子力显微镜(AFM)研究表明,该荧光薄膜表面平整,有望用于制备有机电致发光器件(OLED),可见该化合物是一种多功能材料.     

压致变色聚集诱导发光材料

聚集诱导发光化合物分子具有特殊的螺旋桨形扭曲构象结构, 导致其很难在结晶状态下进行紧密堆砌, 使得其结晶结构容易在外力的作用发生改变, 致使其分子能级水平和发光光谱发生变化, 产生压致发光变色现象. 因此, 聚集诱导发光化合物是压致发光变色材料的一个重要来源. 压致变色聚集诱导发光材料是一类重要的压致发光变色材料, 其既具有压致发光变色的性能, 又具有聚集诱导发光的性能. 它是一类智能材料, 在应力传感、商标防伪和发光器件等领域具有重要的潜在应用, 近年来受到人们极大的关注. 本文分类介绍了近年来压致变色聚集诱导发光材料的研究进展.     

创新型化学实验设计:AIE超支化聚碳酸酯的合成、表征及性质研究

通过对酯化反应、酯交换反应和聚集诱导发光概念的深入介绍以及不同合成超支化聚碳酸酯方法的比较分析,引导学生理解“传统孕育创新”的文化思想。以碳酸二乙酯和丙三醇为原料,通过简单的酯交换缩聚反应设计并合成具有聚集诱导发光效应的超支化聚碳酸酯,利用紫外-可见分光光度计、荧光分光光度计分别研究超支化聚碳酸酯的紫外吸收性能和荧光性能;通过透射电镜和激光粒度仪研究超支化聚碳酸酯的聚集形貌和大小以探索发光机理。整个实验教学从科学角度出发,从合成原理和发光机理的教学理论中让学生理解“传统孕育创新”的文化内涵,不仅可以培养学生对科研的热情和兴趣,还可以让学生掌握先进仪器的操作技能,培养学生综合实验能力和人文素养。     

苯并噻唑酮类热活化延迟荧光材料的合成及其光电性能研究

以苯并噻唑-2-基(苯基)甲酮作为受体,具有强给电子能力的吩噁嗪和吩噻嗪作为给体构筑给体-受体(D-A)型分子,设计合成了两种具有聚集诱导发光(AIE)特性的热活化延迟荧光(TADF)红光材料3和4,并对它们的热稳定性、电化学性质、单晶结构、光物理性质和电致发光性能进行了系统研究.两种化合物具有较小的单三线态能级差(ΔE_ST,0.04和0.16 eV)以及微秒级延迟寿命(0.63和1.30μs),表现出明显的TADF特性.通过对比化合物在粉末状态下研磨前后的发射光谱,发现化合物4具有明显的力致变色发光现象.在纯薄膜下,两种化合物的发射峰分别为683和654 nm,光致发光量子产率(PLQY)分别为0.8%和3.6%.基于化合物3和4的非掺杂有机发光二极管(OLED)器件,均获得了纯红光发射(662和652 nm),器件的最大外量子效率(EQE)分别为0.15%和0.34%.虽然基于这两种化合物的器件发光效率有待提升,但它们的合成过程简便,能为开发苯并噻唑酮类TADF红光材料提供一定的启发.     

三苯胺类小分子的合成及其AIE性能研究

以二苯胺、碘苯、对碘甲苯以及对碘苯甲醚为原料,合成了三苯胺及其衍生物T1~T5(4-甲氧基三苯胺、4-甲基三苯胺、4-醛基三苯胺、4-乙烯基三苯胺),并对其紫外-可见吸收光谱与荧光光谱进行了检测。结果表明,连有甲氧基、甲基、乙烯基取代基的三苯胺化合物在甲醇/氯仿混合溶液中具有聚集诱导发光(AIE)性能;而醛基取代的4-醛基三苯胺表现出了聚集荧光猝灭(ACQ)现象。     

本科生有机化学实验与前沿科学研究的融合—四(4-甲基苯基)乙烯的合成、表征及聚集发光性能研究

四苯乙烯(TPE)及其衍生物,作为一类典型的聚集诱导发光分子,由于其合成简单、易于修饰和发光性能优异等优点,已被广泛的应用于化学生物传感器、生化检测、生物成像和有机光电材料等领域。在此,我们将聚集诱导发光这一前沿研究热点融入有机化学实验教学中,进行教学对象为化学专业本科生的前沿有机化学实验设计：四(4-甲基苯基) 乙烯的合成、表征及聚集发光性能研究。该实验内容包括通过McMurry 偶联反应合成四(4-甲基苯基) 乙烯、四(4-甲基苯基) 乙烯的结构表征,以及利用紫外-可见分光光度计和荧光光谱仪对其聚集诱导发光性能进行研究。通过本实验,使学生了解聚集诱导发光这一科学研究前沿领域,激发学生对科学研究的兴趣、拓展科研视野、激发科研热情、培养学生的科研探究能力。本实验综合了有机化学、仪器分析和发光材料等知识点的学习,培养学生的实验操作技能,提升学生的综合及创新能力,建议纳入高年级中级有机化学实验课程。     

共聚物Poly(DMAEMA-co-TPE-a)的合成及pH敏感荧光多孔光纤制备

将甲基丙烯酸N,N-二甲氨乙酯(DMAEMA)和微量荧光单体4-丙烯酰氧基四苯乙烯(TPE-a)经自由基共聚合制备了共聚物Poly(DMAEMA-co-TPE-a)(PDT),并通过引入交联剂N,N-亚甲基双丙烯酰胺(Bis)和致孔剂N,N-二甲基甲酰胺(DMF)制备了pH敏感荧光多孔光纤。采用FT-IR、~1 H-NMR、TG和SEM表征了产物的结构,研究了产物的荧光和pH响应性能。研究表明,共聚物PDT具有聚集诱导发光(AIE)效应,并具有较好的pH响应性能;当单体、交联剂和致孔剂的物质的量之比为60∶1∶40时,制备的pH敏感荧光多孔光纤具有较好的耐热性能、内部结构和pH响应性能。     

A fluorescent supramolecular crosslinked polymer gel formed by crown ether based host-guest interactions and aggregation induced emission

Based on the combination of B21C7/dialkylammonium salt host-guest interactions and tetraphenylethylene(TPE)-based aggregation-induced emission(AIE) effect, a fluorescent supramolecular crosslinked polymer gel was successfully prepared. Compared with the solution of TPE-containing small molecules, this gel exhibited remarkable fluorescence enhancement due to the AIE effect of TPE units. The "gelation induced fluorescence emission" phenomenon can be explained by the hindered intramolecular rotation of phenyl rings of TPE. Because of the reversibility and stimuli-responsiveness of the B21C7/dialkylammonium salt host-guest interactions, the transition between the fluorescent supramolecular crosslinked polymer gel and the disassembled sol with very weak fluorescence can be realized by adding p H and thermal stimuli. This novel material contributes to the development of supramolecular chemistry, polymer science and fluorescent materials and offers a new method to construct functional supramolecular materials.     

Rational Design of a Near-infrared Fluorescent Material with High Solid-state Efficiency,Aggregation-induced Emission and Live Cell Imaging Property

Near-infrared(NIR) fluorescent materials with high photoluminescent quantum yields(PLQYs) have wide application prospects. Therefore, we design and synthesize a D-A type NIR organic molecule, TPATHCNE, in which triphenylamine and thiophene are utilized as the donors and fumaronitrile is applied as the acceptor. We systematically investigate its molecular structure and photophysical property. TPATHCNE shows high T_gof 110℃ and T_d of 385℃ and displays an aggregation-induced emission(AIE) property. A narrow optical bandgap of 1.65 eV is obtained. The non-doped film of TPATHCNE exhibits a high PLQY of 40.3% with an emission peak at 732 nm, which is among the best values of NIR emitters. When TPATHCNE is applied in organic light-emitting diode(OLED), the electroluminescent peak is located at 716 nm with a maximum external quantum efficiency of 0.83%. With the potential in cell imaging, the polystyrene maleic anhydride(PMSA) modified TPATHCNE nanoparticles(NPs) emit strong fluorescence when labeling HeLa cancer cells, suggesting that TPATHCNE can be used as a fluorescent carrier for specific staining or drug delivery for cellular imaging. TPATHCNE NPs fabricated by bovine serum protein(BSA) are cultivated with mononuclear yeast cells, and the intense intracellular red fluorescence indicates that it can be adopted as a specific stain for imaging.     

Triptycene-scaffolded tetraphenylethylenes with irregular temperature-dependence AIE

A series of new tetraphenylethylene monomer, dimer and three-dimensional trimer based triptycene-bridged triphenylethenes has been constructed. Their structures were clearly confirmed and the irregular fluorescent behaviors at different temperatures and solvents were investigated. Results showed the new tetraphenylethylenes performed remarkable aggregation-induced emission (AIE) properties and the emission intensities are dependent on temperature and viscosity. Compared with the model tetraphenylethylene without connecting triphenylethylene, the fluorescence quantum yields of the titled triptycene-scaffolded tetraphenylethylenes in aggregation are greater than tetraphenylethylene and increased as the increasing of the triphenylethylene units.     

四苯乙烯衍生物的合成、性能及其对铀酰离子的荧光识别

聚集诱导发光(AIE)效应在铀酰离子痕量检测方面具有广阔的应用前景。本文以四苯乙烯(TPE)为母体,设计合成了一种TPE席夫碱类化合物T2,并对其溶液态和聚集态的光学性质进行了表征。结果表明,T2具有AIE特性。并且,当向T2中加入铀酰离子后,体系荧光发射峰从540nm蓝移到500nm,肉眼可见由黄色到黄绿色的明显颜色变化,表明化合物T2可用于检测水体中的铀酰离子。     

Unsymmetrical photochromic bithienylethene-bridge tetraphenylethene molecular switches: Synthesis,aggregation-induced emission and information storage

Aggregation-induced emission(AIE) active photochromic molecules have attracted growing attention for their versatile applications.Here we designed and synthesized five newly unsymmetrical photochromic diarylethene(DAE) dyads(BTE1-5) by connecting tetraphenylethene(TPE) and aromatic substituent via bithienylethene(BTE) bridge.The chemical structures of those compounds were identified by ^1H NMR,¹³C NMR and HRMS.The absorption and emission of these dyads were investigated by UV-vis and fluore scence spectroscopy,respectively.The results showed that all those compounds exhibited typically AIE or aggregation-induced emission enhancement(AIEE) characteristic.Particularly,when an aggregationcaused quenching(ACQ) fluorophore(triphenylamine) was grafted to the molecule,connecting with TPE via BTE-bridge,the ACQ phenomenon was dissipated and converted to an AIE luminophore,and those compounds exhibited photochromism upon irradiation with alternative UV and visible light.The solution or solid of those compounds showed distinctly fluorescence switching "ON" or "OFF" observation upon irradiation with alternative UV and visible light.It is interesting that BTE1 could be applied in recording and rewritable information storage,and the cyclization quantum yields could be affected by substituent significantly.     

聚集态荧光增强的Λ-型异弗乐酮衍生物纳米粒子

本文选择Λ-型TB骨架作为分子的基本框架, 将二腈基异弗乐酮引入其中, 采用简便方法合成了一种具有聚集态荧光增强现象的红光材料2,8-双[2-(5,5-二甲基-环乙烯基-2-烯基)丙二腈]-6H,12H-5,11-甲基二苯[b,f][1,5]二氮芳辛(DMCEM). 同时, 制备了粒径不同的DMCEM纳米颗粒, 并对其光学性质进行了研究.     

Aggregation-induced emission of non-conjugated poly(amido amine)s: Discovering,luminescent mechanism understanding and bioapplication

It is found that the fluorescence of aliphatic poly(amido amine)s including linear and hyperbranched ones can be dramatically enhanced by simple aggregation of polymer chains, attributing to the formation of a variety of intra- and interchain clusters with shared lone-pair electrons and the restriction of intramolecular motions. Thanks to the combination of strong solid fluorescence and excellent biocompatibility, these non-conjugated polymers become promising candidates for bioimaging such as bacterial detection. This finding not only extends the aggregation-induced emission(AIE) systems from conjugated compounds to non-conjugated materials, which expands the bioapplication range of AIE systems, but also sheds light on the exploration of novel unconventional luminogens.     

用水溶性四苯基乙烯基荧光探针检测ctDNA

设计合成了一种水溶性的四苯基乙烯(TPE)衍生物TPEDPyMe,研究了该化合物的吸收和发射特性,发现TPEDPyMe具有聚集诱导发光(AIE)性能.在pH值为7.2的三羟甲基氨基甲烷-盐酸(tris-HCl)缓冲溶液中用TPEDPyMe检测小牛胸腺DNA(ctDNA)时观察到,随着ctDNA的浓度从0μg/mL增大到...     

Aggregation emission properties and self-assembly of conjugated oligocarbazoles

Conjugated oligocarbazoles with a 9,10-divinylanthracene core have been synthesized, and exhibit the transition from aggregation-induced emission (AIE) to aggregation-induced emission enhancement (AIEE) behaviour with extending conjugation length; self-assembly of the Cz4 molecule affords nanorings with high fluorescent efficiency.     

Synthesis and properties of a new AIE macrocyclic emitter with triarylamine backbone

A new macrocyclic AIE emitter composed of triarylamine backbone was successfully synthesized through convenient homocoupling procedure and easily purified by silica gel column chromatography, and recrystallization. The optical and electrochemical properties of the compound have been investigated. Intriguingly, the compound shows dual emission both 423 nm and 505 nm. This result implied that the violet emission was originated from an isolated component of the emitter, whereas the yellowish-green emission simultaneously exhibited AIE nature. The compound exhibits enough thermal stability and high glass transition temperature to be applied for organic devices.