Aggregation-induced emission enhancement in poly(phenylene-ethynylene)s bearing aniline groups

Poly(phenylene ethynylene)s(P1) with 4-vinylaniline pendant groups were successfully prepared by the Sonogashira coupling polymerization between l,4-diethynyl-2,5-bis(pentyloxy)benzene and 4-[2-(2,5-dibromophenyl)vinyl]-aniline. In comparison with its analogue P2 without amino group,the emission of P1 is only enhanced by aggregation when adding n-hexane into its THF solution,exhibiting an aggregation-induced emission enhancement(AIEE) effect.When methanol or water instead of hexane was added into THF solution,P1,however,didn’t show AIEE.The results indicated that amino groups strengthen the inter-chain and intra-chain interactions in P1 and restrict the non-radiative energy transition. This strategy can provide a platform for developing highly sensitive and efficient bio- and chemosensors.     

Vinylpyridine- and vinylnitrobenzene-coating tetraphenylethenes: Aggregation-induced emission (AIE) behavior and mechanochromic property

Two new functionalized tetraphenylethene-based dyes were synthesized, and the enhanced AIE and mechanochrmic properties were evaluated upon grinding-fuming with the transformation from crystal forms to irregular amorphous forms.     

Aggregation-induced emission enhancement (AIEE)-active mechanofluorochromic tetraphenylethene derivative bearing a rhodamine unit

A novel tetraphenylethene derivative with a rhodamine unit was successfully synthesized via high-efficiency Suzuki coupling reaction. The highly solid-state emissive target fluorescent molecule exhibited significative aggregation-induced emission enhancement (AIEE) feature. Furthermore, the luminogen showed reversible mechanochromic luminescence behavior involving color change from orange to red. In addition, the powder X-ray diffraction (XRD) test results verified that the mechanofluorochromic phenomenon of luminogen 1 was attributed to a morphological transformation between the crystalline and amorphous states.     

Perspective: Aggregation-induced emission as an emerging strategy for exploring pharmacokinetics of oral polysaccharides

Clinical application of polysaccharides is severely limited by their various pending and controversial pharmacokinetics problems. Thus, it is urgent to develop accurate detection methods for polysaccharides and their metabolites. Aggregation-induced emission (AIE) is a unique photophysical phenomenon of propeller-shaped molecules. Currently, AIE has been successfully used to realize visualization for gelation process of polysaccharides, and accurate monitoring of spatiotemporal drug release of doxorubicin. In particular, authors found that aggregation event always happens during the pharmacokinetic process. Therefore, it is proposed that AIE can be a promising method for accurate detection of polysaccharides as well as elucidation of their bioavailability.     

水热法制备非共轭聚集诱导发光聚合物及其在Fe^3+检测中的应用

以“自稳定沉淀聚合”制备的聚马来酸酐-醋酸乙烯酯线性交替共聚物(PMV)为原料,利用水热法制得3种新型非共轭聚集诱导发光(AIE)聚合物.通过荧光光谱、紫外-可见光光谱、傅里叶变换红外光谱(FTIR)、X射线光电子能谱分析(XPS)等表征方法,研究了3种聚合物的荧光和结构特性,并考察了其在Fe3+检测的应用.实验结果表明:3种PMV衍生物均具有AIE性质,随着水热时间的延长,聚合物的发光颜色从蓝色红移至黄色,且水热1 h所得产物固体的绝对量子产率最高,可达17.05%;所得非共轭AIE聚合物可用于Fe3+检测,当Fe3+浓度为5~200μmol/L时,猝灭效率与Fe3+浓度符合线性关系,调整确定系数为0.9922,最低检测限可低至1.22μmol/L.     

Strong fluorescence emission from PEGylated hyperbranched poly(amido amine)

Hyperbranched poly(amido amine)s (HPAA) show weak photoluminescence, however, they have shown strong emission after short polyethylene glycol (PEG) chains have been linked onto HPAA macromolecule via Michael addition reaction. These PEGylated hyperbranched poly(amido amine)s show low cytotoxicity and potential application in cell imaging.     

Designing poly(amido amine) dendrimers containing core diversities by click chemistry of the propargyl focal point poly(amido amine) dendrons

General, fast, efficient, and inexpensive methods for the synthesis of poly (amido amine) (PAMAM) dendrimers having core diversities were elaborated. In all syntheses, the major step involved an inexpensive 1,3‐dipolar cycloaddition reaction between an alkyne and an azide in the presence of Cu(I) species, which is known as the best example of click chemistry. The propargyl‐functionalized PAMAM dendrons are obtained by the divergent approach using propargylamine as an alkyne‐focal point. Three core building blocks, 1,3,5‐tris(azidomethyl)benzene, N,N,N′,N′‐tetra(azidopropylamidoethyl)‐1,2‐diaminoethane, and 4,4′‐(3,5‐bis(azidopropyloxy)benzyloxy)bisphenyl, were designed and synthesized to serve as the azide functionalities for dendrimer growth via click reactions with the alkyne‐dendrons. These three building blocks were employed together with the propargyl‐functionalized PAMAM dendrons in a convergent strategy to synthesize three kinds of PAMAM dendrimers with different core units. This novel and pivotal strategy using an efficient click methodology provides the fast and efficient synthesis of the PAMAM dendrimers with the tailed made core units. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1083–1097, 2008     

超支化聚酰胺-胺破乳剂的合成及应用

以N-丙烯酰-1,2-乙二胺盐酸盐(ADE)合成为基础,通过ADE的Michael加成反应制备阳离子超支化聚合物聚N-丙烯酰-1,2-乙二胺盐酸盐(HADE),并对其结构进行了表征。研究表明,50℃下,HADE破乳剂(质量浓度为200 mg/L)对含煤油质量分数5%的水包油(O/W)煤油乳液的除油率可高达95.6%,显示了产品在乳液破乳除油方面良好的发展前景。     

Aliphatic Hyperbranched Poly（amido amine）s （PAMAMs） ： Preparation and Modification

A series of water soluble aliphatic hyperbranched poly(amido amine)s(PAMAMs) with the same or similar chemical structure of poly(amido amine) dendrimer was successfully synthesized from commercially available AB and Cn types of monomers by one-pot polymerization via the couple-monomer methodology(CMM). The AB type monomer used in this paper was methyl acrylate, and Cn monomers were multi-amino compounds such as ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetraamine (TETA). tetraethylenepentaamine (TEPA) and pentaethylenehexamine (PEHA). The reaction mechanism was investigated by means of the mass spectra of the reaction intermediates. Adjusting the feed ratio of AB to Cn. hyperbranched polymers with different terminal groups and properties were obtained. FTIR, NMR, DSC. and TGA were used to characterize the polymers. It was found that the polymers‘ properties such as solubility, thermal behaviour and encapsulation capability varied with changing the feed ratio of AB to Cn. Benzoyl and palmitoyl groups were introduced into these macromolecules by acidylation to form amphiphilic hyperbranched polymers which have a high capability to encapsulate water soluble dyes such as Congo red. It is expected that the hyperbranched PAMAMs can play an important role in the industrial applications, such as coatings, cross-linking and phase-transferring agents because of their versatility and availability.     

Synthesis of carbohydrate‐linked poly(polyoxometalate) poly(amido)amine dendrimers

Mannose‐functionalized and ethoxyethanol‐functionalized poly(amido)amine dendrimers bound multiple vanadate‐substituted polyoxotungstate Wells–Dawson‐type polyoxometalates (POMs). Dendrimers incorporating 10–30 POMs were characterized with NMR, transmission electron microscopy, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry techniques. The number of metal clusters per dendrimer molecule varied according to the dendrimer generation and the nature of the surface functional groups. Efforts aimed at using the poly(polyoxometalate) dendrimers as oxidation catalysts are also described. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3059–3066, 2005     

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。     

Anion detection by aggregation-induced enhanced emission (AIEE) of urea-functionalized tetraphenylethylenes

Substituted tetraphenylethylenes (TPEs) have been prepared that feature four alkyl or aryl urea groups arrayed along the periphery. Exposure of these TPEs to monovalent anions (halide, carboxylate, nitrate, and azide) resulted in enhanced fluorescence emission attributed to aggregation of the TPE molecules via urea-anion hydrogen bonding. Emission enhancement correlated with anion basicity, with fluoride ion eliciting the largest fluorescence response. Increased fluorescence emission could also be detected visually in solutions viewed under UV light. This study demonstrates the feasibility of TPE-based fluorescent anion sensors/detectors, and it is envisioned that additional design modifications may afford anion-selective fluorescent sensors.     

Preparation of mesoporous aluminophosphate using poly(amido amine) as template

Mesoporous aluminophosphate was prepared by using G4.0 poly(amido amine)dendrimer as a template and characterized by Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and N₂ adsorption/desorption methods. Results show that the title compound exhibits a typical mesoporous structure with the average pore size from 5 to 8 nm. The formation mechanism of the nanoporous structure using dendrimer as a template was also discussed. __________ Translated from Journal of Fujian Normal University (Natural Science Edition), 2007, 23(2): 67–70 [译自: 福建师范大学学报 (自然科学版)]     

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.     

Gold nanorods and poly(amido amine) dendrimer thin film for biosensing

Journal of Solid State Electrochemistry - The use of gold nanomaterials in electrochemical biosensing has been proven to be effective either by modifying the electrodes’ surface or by...     

1,2,4,5-四{4-[N,N-二(4-碘苯基)氨基]苯乙烯基}苯的聚集诱导发光增强及电存储性质

通过Wittig-Horner反应合成了1个三苯胺共轭树枝分子1,2,4,5-四{4-[N,N-二(4-碘苯基)氨基]苯乙烯基}苯(TPAB-I). TPAB-I在甲苯、 四氢呋喃、 乙酸乙酯、 二氯甲烷和DMF溶液中的最大荧光发射峰分别位于451, 464, 478, 481和511 nm; 其固体粉末和旋涂膜的最大发射波长分别为526和488 nm. 实验结果表明, TPAB-I具有明显的聚集诱导发光增强效应. 将三苯胺共轭树枝分子TPAB-I用于制作有机电存储器件, 制得了三明治夹心结构的Al/TPAB-I/ITO电存储器件. 该电存储器ON/OFF状态下电流比接近10⁴, 擦除电压为-2.0 V, 写入电压为1.5 V, 在1.0 V的读取电压下, 电存储器在10⁴ s内均能保持良好的稳定性, 具有较好的电存储性能.     

Synthesis and Fluorescent Properties of Biodegradable Hyperbranched Poly(amido amine)s

Disulfide‐functionalized hyperbranched poly(amido amine)s (HPAMAMs) were synthesized by Michael addition polymerization of N,N'‐cystaminebisacrylamide and 1‐(2‐aminoethyl)piperazine. The novel HPAMAMs displayed bright fluorescence, and the emissions bands cover nearly the whole visible wavelength range. When polymer solutions were excited at 330–385, 460–490, and 510–550 nm, blue, green, and red solutions were observed, respectively. The HPAMAMs are biodegradable and they can be easily cleaved by 2‐mercaptoethanol or glutathione, leading to a decrease in the fluorescence intensity. Studies of applications of the biocompatible and biodegradable HPAMAMs in fluorescence imaging technology and biological science are in progress.

     

Aggregation-induced emission active 3,6-bis(1,2,2-triphenylvinyl)carbazole and bis(4-(1,2,2-triphenylvinyl)phenyl)amine-based poly(acrylates) for explosive detection

Four novel aggregation-induced emission (AIE)-active poly(acrylates), in which AIE-active luminogens 3,6-bis(1,2,2-triphenylvinyl)carbazole (BTPC) and bis(4-(1,2,2-triphenylvinyl)phenyl)amine (BTPPA) were linked to the polymer backbone via a flexible alkyl chain, were synthesized in high yields. Spectrofluorometric analysis of polymer nano-aggregates in tetrahydrofuran/water revealed that PTPPA-based polymers gave more sensitive fluorescence response to nitro-aromatics including 2,4,6-trinitrotoluene than BTPC-based polymers. Paper probes were also fabricated for solid-state detection of explosives. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 672–681     

Novel thermally stable poly(amine hydrazide)s and poly(amine‐1,3,4‐oxadiazole)s for luminescent and electrochromic materials

We describe the preparation, characterization, and luminescence of four novel electrochromic aromatic poly(amine hydrazide)s containing main‐chain triphenylamine units with or without a para‐substituted N,N‐diphenylamino group on the pendent phenyl ring. These polymers were prepared from either 4,4′‐dicarboxy‐4″‐N,N‐diphenylaminotriphenylamine or 4,4′‐dicarboxytriphenylamine and the respective aromatic dihydrazide monomers via a direct phosphorylation polycondensation reaction. All the poly(amine hydrazide)s were amorphous and readily soluble in many common organic solvents and could be solution‐cast into transparent and flexible films with good mechanical properties. These poly(amine hydrazide)s exhibited strong ultraviolet–visible absorption bands at 346–348 nm in N‐methyl‐2‐pyrrolidone (NMP) solutions. Their photoluminescence spectra in NMP solutions or as cast films showed maximum bands around 508–544 and 448–487 nm in the green and blue region for the two series of polymers. The hole‐transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. All obtained poly(amine hydrazide)s and poly(amine‐1,3,4‐oxadiazole)s exhibited two reversible oxidation redox couples at 0.8 and 1.24 V vs. Ag/AgCl in acetonitrile solution and revealed excellent stability of electrochromic characteristics, changing color from original pale yellow to green and then to blue at electrode potentials of 0.87 and 1.24 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3245–3256, 2005     

Structural investigations of poly(amido amine) dendrimers in methanol using molecular dynamics

The molecular structure of poly(amido amine) dendrimers is investigated with molecular dynamics simulations using the Amber 7 modeling package. A method for defining residues for complex molecules is developed, and it enables the study of the effects of protonation of the primary and tertiary amines. The effects of implicit solvents versus explicit solvents as well as the pH of the solution on the molecular structure are calculated. Good agreement with experimental results for the radius of gyration measured in methanol by X‐ray scattering is observed for simulations with an explicit solvent and protonation of the primary amines. Calculations of the intramolecular atomistic pair correlation function show a dense core, as well as the presence of voids filled with the solvent inside the molecule. The primary amines (end groups) are shown to access the molecular interior by backfolding. Comparisons with experiments and other reported simulation results highlight the advantages of the approach developed here. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3062–3077, 2006