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...     

基于六苯基苯骨架四苯基乙烯衍生物的合成及聚集诱导发光性质研究

设计合成了三个基于六苯基苯骨架结构的四苯基乙烯衍生物HPB-nTPE (n=2, 4, 6), 它们的分解温度均在440 ℃以上, 具有很好的热稳定性. 研究了化合物的均相溶液、聚集体以及固体粉末的光物理性质. 该类化合物具有典型的聚集诱导发光性质, 在均相溶液中几乎不发光, 而形成聚集体后发出明亮的蓝绿色荧光, 荧光量子产率分别为0.37, 0.36和0.37, 与均相溶液中相比增强了400多倍. HPB-nTPE固态呈无定形结构, 荧光量子产率分别为0.39, 0.36和0.36, 约为固态四苯基乙烯的1.8倍. HPB-nTPE的聚集态和固态的高发光量子产率来自两方面的贡献, 一是凝聚态抑制了四苯基乙烯基团中苯环的自由旋转引起的激发态非辐射跃迁, 另一方面是星形刚性六苯基苯骨架进一步抑制了凝聚态分子内和分子间四苯基乙烯基团π-π堆积引起的激发态非辐射跃迁过程, 从而提高了四苯基乙烯基团的辐射跃迁效率. 本研究对高效有机光功能材料的发展有重要意义.     

硅烷桥联四苯乙烯-寡聚噻吩衍生物的结构与光谱性质（英文）

设计合成了一系列硅烷桥联四苯乙烯(TPE)-寡聚噻吩衍生物.硅烷取代基为甲基和苯基,寡聚噻吩单元中噻吩数量为1～3,通过空间位阻效应和电子效应调控分子的固态发光性质.具有苯基取代基的硅烷和二噻吩分子表现出高达64.5%的固态发光.含1或2个噻吩单元的分子的固态和液态荧光性质类似四苯乙烯,而含3个噻吩的分子的发光则主要来自于三噻吩,其在液态和聚集态分别有1.4%和14%的发光效率.苯基硅烷桥联三噻吩-四苯乙烯分子的聚集体具有检测硝基爆炸物的能力和防伪应用潜力.     

插烯噁唑类化合物的研究(Ⅰ)——反-1,2-双[2′-(5′-苯基噁唑基)]乙烯及其衍生物的合成与光性能的研究

本文合成了12种反-1,2-双[2’-(5’-苯基嚼唑基)]乙烯(简称POEOP)及其衍生物。讨论了化合物的结构同其红外光谱、紫外光谱、荧光光谱、荧光量子产率及激光转换效率间的关系,并与POOP类化合物的光性能进行了比较。     

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...     

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。     

一种推拉型A-D-A蒽衍生物的合成、多光子吸收及荧光性质

一种推拉型A-D-A蒽衍生物9,10-二{4-{2-N,N-二{4-{4-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]苯乙烯基}苯基}胺基}苯乙烯基}蒽(An-BPOAS)由四碘代芳香化合物9,10-二{4-[N,N-二(4-碘苯基)氨基]苯乙烯基}蒽(An-BIPAS)与芳基乙烯通过钯催化Heck偶联反应制备.用飞秒Ti:sapphire激光测定了9,10-二芳基蒽树形分子An-BPOAS的多光子吸收系数和多光子诱导荧光光谱.在1300 nm飞秒激光激发下,An-BIPAS和An-BPOAS的三光子荧光峰分别位于553和539 nm.1300 nm飞秒激光激发下采用非线性透过率法测得An-BIPAS和An-BPOAS的三光子吸收系数分别为0.3×10-5和1.5×10-5 cm3/GW2.测定了树形分子An-BPOAS的线性吸收和荧光性质.实验测定了不同pH值化合物An-BPOAS在DMF/H2O混合溶液中的荧光光谱.化合物An-BPOAS具有良好的荧光性能,可作为性能良好的双光子及三光子吸收及荧光材料.     

聚集诱导发光有机氟化合物的研究进展

聚集诱导发光(aggregation-induced emission, AIE)化合物因在生物和化学传感、发光材料、显示等领域具有重要价值而备受关注.作为一类重要的功能分子,有机氟化合物在化学和材料等领域被广泛研究.汇总了具有聚集诱导发光性质的有机氟化合物,并进行了分类讨论.AIE有机氟化合物包括氟代的四苯基乙烯(TPE)衍生物、二苯乙烯基蒽(DSA)衍生物、氰基二苯基乙烯衍生物和二苯乙烯基苯衍生物等常见的AIE化合物,也包括聚合物、碳硼烷簇合物和室温磷光化合物,还有其它一些含氟结构.AIE化合物氟代后,稳定性一般会提高,氟原子参与分子间相互作用,导致聚集态的结构发生改变,从而导致发光性质的改变,如发光增强、发光波长红移(蓝移)或发光量子效率及发光寿命提高等.最后,对AIE有机氟化合物的研究前景进行了展望.     

读者园地

问:见到有两种分子结构不同的苯基荧光酮试剂,但它们的简称都是二溴苯基荧光酮,为什么?湖南读者———马辉　　　　答:将苯基荧光酮(Phenylfluorone)的分子结构式和问题中的两种化合物的可能分子结构式图示如下:图1　苯基荧光酮及两种衍生物的结构式Fig .1　StructuralformulaofPFanditstwoderivatives化合物(a)的化学命名应为2 ,3,7 三羟基 9 苯基 6 荧光酮,简称苯基荧光酮(简写作PF)。化合物(b)应命名为2 ,3,7 三羟基 4 ,5 二溴 9 苯基 6 荧光酮,可简称为二溴苯基荧光酮(简写作DBPF)。化合物(c)应命名为2 ,3,7 三羟基 9 (3′,5′…     

2,4和8-支噁二唑衍生物的三光子吸收和三光子上转换荧光

用飞秒Ti:sapphire激光测定了3个对称噁二唑衍生物4-{N,N-双[4-(4-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]苯乙烯基)苯基]氨基}苯甲醛(Bis-oxa)、2,5-双{4-[2-N,N-双(4-{4-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]苯乙烯基}苯基)氨基苯乙烯基]苯基}-1,3,4-噁二唑(Quadri-oxa)和2,5-双(4-{2-N,N-双[({3,5-二[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]苯基}乙烯基)苯基]氨基苯乙烯基}苯基)-1,3,4-噁二唑(Octu-oxa)的三光子吸收谱和三光子荧光光谱. 在1260 nm飞秒激光激发下, 2,4和8-支噁二唑衍生物的三光子吸收系数分别为5.0×10^-5, 10.0×10^-5和10.0×10^-5 cm³/GW², 三光子频率上转换荧光发射波长分别为533, 544和551 nm. 研究了多支化合物线性吸收和透过、单光子荧光及量子产率、荧光寿命、多光子荧光光谱和三光子吸收系数谱. 对称多支噁二唑衍生物具有很强的三光子吸收和上转换荧光性质.     

Aggregation-induced emission of tetraphenylethene derivative as a fluorescence method for probing the assembling/disassembling of amphiphilic molecules

The aggregation-induced emission (AIE) of a 1,2-diphenyl-1,2-di(p-tolyl)ethene (TPE) was explored as a novel fluorescence method for probing the assembling/disassembling of amphiphilic molecules. The fluorescence intensity was able to monitor the formation of micelles and determine the critical micelle concentration (CMC) of surfactants. The temperature-dependent micellization of the pharmaceutically important PEO-PPO-PEO copolymer, Pluronic F127, was further studied by using the TPE fluorescence spectrum intensity. Our results showed good agreement with those reported in the literature by using other methods. The special advantage of the AIE probe method was further explored to determine the assembling/disassembling process of the colored amphiphilic molecule, 1-[4-(3-phenylazophenoxy)butyl]triethylamine bromide (AzoC4), whose CMC value has not previously been described. Since the TPE fluorescence signal mainly comes from the aqueous phase, not from the inside of hydrophobic core, it provides a possible platform to study the CMC of those colored surfactants. Based on the novel fluorescence properties of TPE in the aggregated and dispersed states, one can conclude that the TPE method is a promising method for the determination of the CMC and critical micellization temperature (CMT), particularly having a special advantage to determine the assembling/disassembling process of colored amphiphilic molecules.     

Theoretical study on the aggregation-induced emission mechanism of anthryl-tetraphenylethene

Since the concept of aggregation-induced emission (AIE) was proposed by Benzhong Tang's research group in 2001, the exploration of the mechanism of AIE and the development of new high-performance AIE materials have been the focus and goal of this field. On the basis of a large number of experiment results, AIE mechanism has been well explained by lots of works, such as restricted intramolecular motion (RIM), J-aggregate et al. As tetraphenylethlene (TPE) molecules are stacked, the rotation of the benzene ring rotor is blocked, and the energy attenuation is released in the form of radiation, showing the AIE effect. In order to further explore the AIE effect of TPE, we performed electronic structure, spectrum simulation, and AIE mechanism calculations of the anthryl-tetraphenylethene (TPE-an) monomer and dimer in the gas phase, tetrahydrofuran (THF), and aqueous solutions at the B3LYP/6-31G** level. The calculation results show that TPE-an molecule is in a propeller-like configuration, and its fluorescence intensity is weak; compared with the monomer, the fluorescence intensity of the dimer increases by 87% in aqueous solution; the fluorescence intensity in the gas phase, THF solution, and aqueous solution gradually enhances with the increase of the degree of aggregation, which are consistent with the experimental results. The enhancement of fluorescence intensity is caused by the change of molecular structure caused by aggregation. This detailed AIE luminescence mechanism will provide theoretical guidance for AIE material design.     

Mapping Live Cell Viscosity with an Aggregation‐Induced Emission Fluorogen by Means of Two‐Photon Fluorescence Lifetime Imaging

Intracellular viscosity is a crucial parameter that indicates the functioning of cells. In this work, we demonstrate the utility of TPE‐Cy, a cell‐permeable dye with aggregation‐induced emission (AIE) property, in mapping the viscosity inside live cells. Owing to the AIE characteristics, both the fluorescence intensity and lifetime of this dye are increased along with an increase in viscosity. Fluorescence lifetime imaging of live cells stained with TPE‐Cy reveals that the lifetime in lipid droplets is much shorter than that from the general cytoplasmic region. The loose packing of the lipids in a lipid droplet results in low viscosity and thus shorter lifetime of TPE‐Cy in this region. It demonstrates that the AIE dye could provide good resolution in intracellular viscosity sensing. This is also the first work in which AIE molecules are applied in fluorescence lifetime imaging and intracellular viscosity sensing.     

Fluorometric sensing of biogenic amines with aggregation-induced emission-active tetraphenylethenes

A fluorometric sensor for detection and identification of biogenic amines with carboxylic acid modified tetraphenylethenes (TPEs) based on aggregation-induced emission (AIE) is reported. A mixture of the carboxylic acid substituted TPE and biogenic amines displayed a blue emission on aggregation, which serves as a "turn-on" fluorescent sensor for the amines, the degree of fluorescence enhancement being dependent on the amine. The chromic responses were utilized to distinguish the amines. A fluorometric sensor array of three TPEs with carboxylic acid groups was shown to identify accurately 10 different amines, including biogenic amines. The response patterns were systematically classified by using linear discriminant analysis (LDA) with 98% classification accuracy. Additional information on the concentration of histamine in a "tuna fish matrix" as an example was assessed by the further analysis of the fluorescence intensity, demonstrating a test for food freshness and quality.     

A multifunctional aggregation-induced emission (AIE)-active fluorescent chemosensor for detection of Zn2+ and Hg2+

An aggregation-induced emission (AIE)-active fluorescent chemosensor based on a tetraphenylethene (TPE) unit has been successfully designed and synthesized. Interestingly, the luminogen could detect Zn²⁺ selectively in a THF solution with the detection limit of 1.24 × 10⁻⁶ mol L⁻¹. Meanwhile, the luminogen could also detect Hg²⁺ selectively in a THF-water mixture with the water content of 90%, and the detection limit was 2.55 × 10⁻⁹ mol L⁻¹. Furthermore, the solid-state mechanochromic fluorescence behavior of the luminogen was investigated systematically. Indeed, the AIE-active luminogen also exhibited reversible mechanofluorochromic phenomenon involving fluorescent color change from blue to green, and powder X-ray diffraction results indicated that the switchable morphology conversion between crystalline and amorphous states was responsible for this mechanochromism phenomenon.     

Protein detection and quantitation by tetraphenylethene-based fluorescent probes with aggregation-induced emission characteristics

Three functionalized derivatives of tetraphenylethylene (TPE), namely, 1,2-bis(4-methoxyphenyl)-1,2-diphenylethene (1), 1,2-bis(4-hydroxyphenyl)-1,2-diphenylethene (2), and 1,2-bis[4-(3-sulfonatopropoxyl)phenyl]-1,2-diphenylethene sodium salt (3), were synthesized and their fluorescence properties were investigated. All the TPE molecules are nonluminescent in the solution state but are induced to emit efficiently by aggregate formation. This novel process of aggregation-induced emission (AIE) is rationalized to be caused by the restriction of intramolecular rotations of the dye molecules in the aggregate state. The possibility of utilizing the AIE effect for protein detection and quantification is explored using bovine serum albumin (BSA) as a model protein, with salt 3 being found to perform as a stable, sensitive, and selective bioprobe.     

AIE荧光聚合物RAFT可控合成与表征及光物理性质研究

聚集诱导发光(AIE)分子是与传统的聚集态荧光淬灭染料分子具有截然相反的光物理性质的新型有机发光材料,可广泛应用于化学/生物传感、生物探针与成像、诊疗一体化和光电子器件等诸多领域中。本论文通过可逆加成-断裂链转移(RAFT)聚合方法,可控合成了侧链型四苯乙烯TPE聚丙烯酸酯AIE聚合物。通过实验条件的优化与探索,尤其采用半衰期较短、活性更高的偶氮二异庚腈(ABVN)取代常规的偶氮二异丁腈(AIBN)引发剂,将原来超过12 h的过夜反应前沿科研实验,改造为较短的3–5 h聚合反应时间内即可达到中等收率和较好的聚合物产品质量,使其成为一个适合本科教学环境的新创实验。本实验融合了无水无氧操作技术、柱层析分离纯化、RAFT可控聚合和GPC分子表征技术、FTIR、NMR、UV-Vis、荧光光谱等多种现代实验技术和表征方法,考查了所合成四苯乙烯TPE侧基的AIE聚合物的光物理性质,测定其溶液中的相对荧光量子产率达17%。     

Synthesis and Design of Aggregation‐Induced Emission Surfactants: Direct Observation of Micelle Transitions and Microemulsion Droplets

The direct visualization of micelle transitions is a long‐standing challenge owing to the intractable aggregation‐caused quenching of light emission in the micelle solution. Herein, we report the synthesis of a surfactant with a tetraphenylethene (TPE) core and aggregation‐induced emission (AIE) characteristics. The transition processes of surfactant micelles and the microemulsion droplets (MEDs) formed by the surfactant with a TPE core were clearly visualized by a high‐contrast fluorescence imaging method. The fluorescence intensity of the MEDs decreased as the size of MEDs increased as a result of weakening of the restriction of intramolecular rotation (RIR). The results of this study deepen our understanding of micelle‐transition processes and provide solid evidence in favor of the hypothesis that the AIE phenomenon has its origin in the RIR of fluorophores in the aggregate state.     

Aggregation-induced multicolor luminescent nanoparticles with adaptive and fixed cores derived from brominated tetraphenylethene-containing block copolymer

Aggregation-induced emission (AIE)-active nanoparticles (NPs) exhibiting multicolor fluorescence and high-quantum yields independent of the environment are important for the further development of next-generation smart fluorescent materials. In this work, AIE-active amphiphilic block copolymers were designed and synthesized by RAFT polymerization of a brominated tetraphenylethene (TPE)-containing acrylate (A-TPE-Br). The block copolymer exhibited typical AIE effects in selective solvents, which can be explained by hydrophobic TPE aggregated in the core during micelle formation. Luminescent core–shell NPs with a crosslinked AIE core (fixed structure) were synthesized by the Suzuki coupling reaction of the bromine groups of the assembled block copolymer and boronic acid compounds. The NPs composed of TPE/thiophene crosslinked core showed green emission in both diluted state and solid state, implying the ability to fluoresce regardless of environmental changes and molecular dispersion. Multicolor luminescent NPs capable of changing color from blue to red were synthesized by changing the coupling compounds, such as anthracene for electron-rich units and benzothiadiazole for electron-deficient units. The effects of the nature of the donor and acceptor, as well as their combination (TPE/donor/acceptor sequence), on the color and fluorescent intensity of the core crosslinked NPs in the nonpolar and polar solvents, and solid state, were investigated.     

Tetraphenylethylene and N-isopropylacrylamide block polymer-grafted carbon dots with their application in cellular imaging

Carbon dots (CDs) grafted with block polymer of tetraphenylethylene (TPE) and N-isopropylacrylamide (CD-g-poly(TPE-block-NIPAM)) were synthesized, which are aggregation-induced emission (AIE) nanoparticles. The CD-g-poly(TPE-block-NIPAM) exhibited different fluorescence behaviors in tetrahydrofuran (THF) and water. In THF, the CD-g-poly(TPE-block-NIPAM) could fluoresce, but only from CDs, and the TPE block showed no fluorescence. The fluorescence of CDs was quenched ,and the TPE block showed AIE, when the CD-g-poly(TPE-block-NIPAM) were dispersed in water. The CD-g-poly(TPE-block-NIPAM) showed no cytotoxicity, which could be easily internalized by human breast cancer cells and human embryonic kidney cells with high fluorescence, and they can be used as fluorescent tracers for living cells.