Publications by authors named "Hai-Tao Feng"

22 Publications

  • Page 1 of 1

A synergy between the push-pull electronic effect and twisted conformation for high-contrast mechanochromic AIEgens.

Mater Horiz 2021 Feb 15;8(2):630-638. Epub 2020 Dec 15.

AIE Research Center, Shaanxi Key Laboratory of Phytochemistry, College of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji 721013, China.

Mechanochromic (MC) luminogens in response to external stimulus have shown promising applications as pressure sensors and memory devices. Meanwhile, research on their underlying mechanism is still in the initial stage. Here, three pyridinium-functionalized tetraphenylethylenes bearing n-pentyloxy, hydrogen and nitro groups, namely TPE-OP, TPE-H and TPE-NO, are designed to systematically investigate the influence of the push-pull electronic effect and molecular conformation on MC luminescence. Upon anisotropic grinding and isotropic hydrostatic compression, TPE-OP with strong intramolecular charge transfer (ICT) affords the best MC behavior among them. Analysis of three polymorphs of TPE-H clearly indicates that planarization of the molecular conformation plays an important role in their bathochromic shifts under mechanical stimuli. Theoretical calculations also verify that high twisting stress of AIEgens can be released under high pressure. This study presents a mechanistic insight into MC behaviour and an effective strategy to achieve high-contrast MC luminescence.
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http://dx.doi.org/10.1039/d0mh01251cDOI Listing
February 2021

Enantioselective recognition of chiral acids by supramolecular interactions with chiral AIEgens.

Chem Commun (Camb) 2021 Nov 23. Epub 2021 Nov 23.

Shenzhen Institute of Aggregate Science and Technology, School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China.

Novel chiral AIEgens bearing optically pure amino groups were synthesized and showed excellent discrimination for a series of chiral acidic compounds and amino acids. Interestingly, after supramolecular assembly with 4-sulfocalix[4]arene, the obtained complexes showed enhanced enantioselectivity for chiral acids.
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http://dx.doi.org/10.1039/d1cc05618bDOI Listing
November 2021

Glycopeptide-Conjugated Aggregation-Induced Emission Luminogen: A pH-Responsive Fluorescence Probe with Tunable Self-Assembly Morphologies for Cell Imaging.

J Phys Chem B 2021 09 8;125(36):10224-10231. Epub 2021 Sep 8.

CAS Center for Excellence in Nanoscience, CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology (NCNST), University of Chinese Academy of Sciences, No. 11 Beiyitiao, Zhongguancun, Beijing 100190, China.

pH values play an important role in various cell biological processes. Abnormal pH values in living systems are frequently associated with the development of diseases such as cancers, infection, and other diseases. Real-time monitoring of the changes of pH values will give us the significant indication for these diseases' progression. Within those pH-sensitive imaging probes, aggregation-induced emission (AIE) molecules exhibit great potential in aqueous imaging environment due to their high fluorescence quantum yield and stability. However, the modulation of the AIE probe with pH sensitivity and light-up property face challenges. Here, we introduced a new glycopeptide-modified AIE probe () based on the optimized solid-phase peptide synthesis approach. The response to pH of the peptide: DDDD progression changed hydrophobicity and hydrophilicity, resulting in the change of the amphipathicity balance. When modulating the pH from 5.5 to 8.0, the adverse protonation of the peptide induced assembled nanostructure transformation from nanolamellae to nanomicelles. Meanwhile, the pH-induced charge change in peptides can greatly influence the microenvironment of the AIEgen, resulting in the increase of fluorescence intensity.
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http://dx.doi.org/10.1021/acs.jpcb.1c06443DOI Listing
September 2021

Substitution Activated Precise Phototheranostics through Supramolecular Assembly of AIEgen and Calixarene.

J Am Chem Soc 2020 09 3;142(37):15966-15974. Epub 2020 Sep 3.

Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & Reconstruction, Institute for Advanced Study, Department of Chemical and Biomedical Engineering, Division of Life Science, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.

Photodynamic therapy (PDT) is a promising noninvasive therapeutic technique and has attracted increasing interests in preclinical trials. However, the translation from laboratory to clinic often encounters the problem of undesired dark cytotoxicity of photosensitizers (PSs). Now, this challenge can be addressed by cascaded substitution activated phototheranostics using the host-guest strategy. Through electrostatical complexation of pyridinium-functionalized tetraphenylethylene, namely, TPE-PHO, and water-soluble calixarene, the dark cytotoxicity of TPE-PHO is dramatically inhibited. The nanoassemblies of the complex show enhanced biocompatibility and selectively locate at the cytoplasm in vitro. When TPE-PHO is competitively displaced from the cavity of calixarene by 4,4'-benzidine dihydrochloride at the tumor site, its dark cytotoxicity and photoactivity in tumor tissue are restored to give efficient PDT efficacy under light irradiation. The result from cell imaging reveals that TPE-PHO undergoes translocation from cytoplasm to mitochondria to kill the cancer cells during the cascaded supramolecular substitution process. In vivo tumor imaging and therapy are successfully implemented to evaluate the curative effect. Such a supramolecular strategy avoids tedious molecular synthesis and opens a new venue to readily tune the PS behaviors.
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http://dx.doi.org/10.1021/jacs.0c06872DOI Listing
September 2020

Tuning Push-Pull Electronic Effects of AIEgens to Boost the Theranostic Efficacy for Colon Cancer.

J Am Chem Soc 2020 07 16;142(26):11442-11450. Epub 2020 Jun 16.

Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration & Reconstruction, Institute for Advanced Study, Department of Chemical and Biomedical Engineering, Division of Life Science, State Key Laboratory of Molecular Neuroscience, and Institute of Molecular Functional Materials, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.

Colon cancer is one of the most common cancers with high mortality in humans. Early diagnosis and treatment of colon cancer is of great significance for cancer therapy. Numerous theranostic agents have been developed to detect and kill cancer cells. However, few reports have focused on how these agents control and affect the gene expression of cancer cells in vivo. Herein, three pyridinium-functionalized tetraphenylethylene derivatives, namely, TPE-OM, TPE-H, and TPE-NO, with electron-donating and electron-withdrawing groups were facilely synthesized as theranostic agents for cell imaging and anticolon cancer therapy. Among these AIE luminogens (AIEgens), TPE-OM with donor and acceptor structure showed the best treatment efficacy for colon cancer through systematic biological evaluation and comparison. Both in vitro cell imaging and in vivo tumor treatment experiments demonstrated that TPE-OM can be utilized as an efficient theranostic agent to diagnose and kill colon cancer cells. Flow cytometric analysis revealed that the cell cycle process was disturbed by TPE-OM in colon cancer cells. Deep insight into the gene level revealed that the expressions of cell-cycle-promoting genes was inhibited upon addition of TPE-OM. This study may open a new venue for unraveling the mechanisms of cancer metastasis.
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http://dx.doi.org/10.1021/jacs.0c02434DOI Listing
July 2020

Tuning molecular emission of organic emitters from fluorescence to phosphorescence through push-pull electronic effects.

Nat Commun 2020 May 26;11(1):2617. Epub 2020 May 26.

Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, 999077, Kowloon, Hong Kong, China.

Organic emitters with persistent phosphorescence have shown potential application in optoelectronic devices. However, rational design and phosphorescence tuning are still challenging. Here, a series of metal-free luminophores without heavy atoms and carbonyl groups from commercial/lab-synthesized carbazole and benzene were synthesized to realize tunable molecular emission from fluorescence to phosphorescence by simply substituent variation. All the molecules emit blue fluorescence in both solution and solid state. Upon removal of excitation source, the fluorinated luminophores show obvious phosphorescence. The lab-synthesized carbazole based molecules exhibit a huge lifetime difference to the commercially purchased ones due to the existence of isomer in the latter samples. The small energy gap between singlet and triplet state and low reorganization energy help enhance intersystem crossing to contribute to a more competitive radiative process from triplet to ground state. Blue and white organic light-emitting devices are fabricated by using fluorinated luminophore as emitting layer.
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http://dx.doi.org/10.1038/s41467-020-16412-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7251133PMC
May 2020

Macrocycles and cages based on tetraphenylethylene with aggregation-induced emission effect.

Chem Soc Rev 2018 Oct;47(19):7452-7476

Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, China.

Organic molecules with an aggregation-induced emission (AIE) effect have recently been attracting more and more attention due to their colossal potential in solid emitters and chemo/biosensors. The number and variety of AIEgen compounds are expanding very rapidly to obtain better application performance and a wider area of application. Among AIEgen systems, tetraphenylethylene (TPE) and its derivatives are the class that have received the most extensive study and the most rapid development because of their facile synthesis. Due to its C2 symmetry and at least tetratopic reaction positions, the TPE unit is also an ideal building block for constructing macrocycles and cages. The resultant cyclic TPE compounds have exhibited many exceptional performances that are difficult to access in their open chain counterparts, such as AIE enhancement, improvement in selectivity and sensitivity as sensors, emission tuning by guests, supramolecular catalysis, further disclosure of the AIE mechanism, molecular adsorption, storage and release, the propeller-like conformation exploitation of the TPE unit in chiral materials and so on. Recently, therefore, a large variety of studies about the synthesis, properties and application research of TPE macrocycles and cages have been reported. These TPE macrocycles and cages significantly expand the research area for the AIE phenomenon and its applications, and represent a development of the AIE area. However, up to now, no review of TPE macrocycles and cages has been available. Thus, this review serves as a summary of the designs, synthesis, photophysical properties, self-assembly, applications and prospects of TPE macrocycles and cages.
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http://dx.doi.org/10.1039/c8cs00444gDOI Listing
October 2018

Dual fluorescence of tetraphenylethylene-substituted pyrenes with aggregation-induced emission characteristics for white-light emission.

Chem Sci 2018 Jul 31;9(25):5679-5687. Epub 2018 May 31.

Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Institute for Advanced Study and Department of Chemical and Biological Engineering , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong , China . Email:

This article presents a new strategy to achieve white-light emission from single tetraphenylethylene-substituted pyrenes (TPE-Pys) with aggregation-induced emission (AIE) characteristics. TPE-Pys were synthesized by a Pd-catalyzed coupling reaction of a boronic acid or pinacol ester of pyrene and tetraphenylethylene (TPE) derivatives and showed multicolor emission by introducing different substituents on the phenyl rings of TPE. TPE-Pys with a TPE unit at the 1-position and asymmetric TPE units at 2,7-positions show dual fluorescence in THF/water mixtures to realize white-light emission with CIE coordinates of ( = 0.30 and = 0.41) and ( = 0.21 and = 0.16), respectively. The structure-property relationship of TPE-Pys were investigated to elucidate the origin of the white emission. The results showed that due to the weak electronic interaction of pyrene and its chromophoric units at the 2,7-positions and the constraint of the rotation of the TPE unit at the 1-position of pyrene, each component can exhibit its own emission color. The combination of appropriate colors gives rise to white-light emission. Such a principle of molecular design may open a new avenue for preparing advanced multicolor and multifunctional optical materials for organic electronics.
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http://dx.doi.org/10.1039/c8sc01709cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6050622PMC
July 2018

Tetraphenylethylene Foldamers with Double Hairpin-Turn Linkers, TNT-Binding Mode and Detection of Highly Diluted TNT Vapor.

Chemistry 2018 Feb 16;24(8):2004-2012. Epub 2018 Jan 16.

Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.

Tetraphenylethylene (TPE) foldamers with double hairpin-turn linkers showing an aggregation-induced emission (AIE) effect have been synthesized for the first time. A crystal structure of a foldamer-TNT complex has been obtained, enabling unprecedented direct observation of the interactions between TNT molecules and the chromophores of the foldamer. Instead of π-π stacking interactions, which have often been considered to be the key mechanism in the binding of TNT by chromophoric receptors, strong n-π interactions between the nitro groups of TNT and the aromatic rings of the foldamer have been found. Exceptionally, by addition of 1 % NaF to a suspension of the foldamer in H O/THF (95:5), the fluorescence quenching efficiency by TNT vapor significantly increased from about 20 % to more than 90 %. Even after diluting TNT-saturated air at 25 °C by a factor of 2×10 , an obvious quenching response was observed, indicating that ultratrace TNT vapor (down to 3.4 fg per mL of air) could be detected.
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http://dx.doi.org/10.1002/chem.201705346DOI Listing
February 2018

Hypaconitine inhibits TGF-β1-induced epithelial-mesenchymal transition and suppresses adhesion, migration, and invasion of lung cancer A549 cells.

Chin J Nat Med 2017 Jun;15(6):427-435

State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China. Electronic address:

Epithelial-mesenchymal transition (EMT) has been implicated in tumor invasion and metastasis and provides novel strategies for cancer therapy. Hypaconitine (HpA), a diester-diterpenoid alkaloid isolated from the root of the Aconitum species, exhibits anti-inflammatory, analgesic, and especially, cardiotoxic activities. Here, we reported the anti-metastatic potentials of HpA in transforming growth factor-β1 (TGF-β1)-induced EMT in lung cancer A549 cells. The cytotoxic effect of HpA was determined by MTT assay. A549 cells were treated with TGF-β1 with or without HpA co-treatment, and the morphological alterations were observed with a microscopy. The expression of E-cadherin, N-cadherin, and NF-κB was determined by both Western blotting and immunofluorescence analyses. The adhesion, migration, and invasion were detected with Matrigel, wound-healing, and transwell assays, respectively. The expression of Snail was determined by Western blotting. The expression of NF-κB p65, IκBα, and p-IκBα in nuclear and cytosolic extracts was assessed by Western blotting. The results showed that low concentration of HpA (<16 μmol·L) had no obvious cytotoxicity to A549 cells. Morphologically, TGF-β1 treatment induced spindle-shaped alteration in the cells. The upregulation of N-cadherin, NF-κB, and Snail and the downregulation of E-cadherin were detected after TGF-β1 treatment. The adhesion, migration and invasion abilities were also increased by TGF-β1. Besides, TGF-β1 induced expression of Snail in a time-dependent manner. Furthermore, TGF-β1 induced nuclear translocation of NF-κB p65. All these alterations were dramatically inhibited by HpA co-treatment. In addition, the NF-κB inhibitor PDTC showed similar inhibitory effect. In conclusion, these results showed that HpA inhibited TGF-β1-induced EMT in A549 cells, which was possibly mediated by the inactivation of the NF-κB signaling pathway, providing an evidence for anti-cancer effect of HpA.
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http://dx.doi.org/10.1016/S1875-5364(17)30064-XDOI Listing
June 2017

Selective Host-Guest Co-crystallization of Pyridine-Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co-crystals.

Chemistry 2017 01 5;23(3):644-651. Epub 2016 Dec 5.

Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.

Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.
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http://dx.doi.org/10.1002/chem.201604133DOI Listing
January 2017

The Fixed Propeller-Like Conformation of Tetraphenylethylene that Reveals Aggregation-Induced Emission Effect, Chiral Recognition, and Enhanced Chiroptical Property.

J Am Chem Soc 2016 09 30;138(36):11469-72. Epub 2016 Aug 30.

Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.

The propeller-like conformation of tetraphenylethylene (TPE) with aggregation-induced emission (AIE) effect was partially and completely fixed by intramolecular cyclization for the first time. The immobilization of propeller-like conformation was found to show great advantages in determining the enantiomer purity, identifying the chiral amines. The completely fixed conformers are resolved into M- and P-enantiomer, which showed mirror imaged CD and almost quantitative fluorescence quantum yield. Furthermore, it also showed a mirror and large circularly polarized luminescence dissymmetric factor, depending on the helicity of the enantiomer. The result provides the most direct and persuasive evidence for AIE via the restriction of intramolecular rotation and finds the new insight of the compounds in chiroptical property.
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http://dx.doi.org/10.1021/jacs.6b07087DOI Listing
September 2016

Enantioselective Recognition for Many Different Kinds of Chiral Guests by One Chiral Receptor Based on Tetraphenylethylene Cyclohexylbisurea.

J Org Chem 2016 05 8;81(9):3720-6. Epub 2016 Apr 8.

Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan, People's Republic of China.

A neutral chiral receptor based on TPE cyclohexylbisurea was synthesized and could discriminate the enantiomers of many different kinds of chiral reagents, including chiral acidic compounds, basic compounds, amino acids, and even neutral alcohols. The (1)H NMR spectra disclosed that the ability of chiral recognition could be ascribed to the multiple hydrogen bonds and CH-π interactions between the TPE urea receptor and the enantiomer of the chiral guest, which led to the selective aggregation of the receptor with one of the two enantiomers. This result exhibited a great potential in enantiomer discernment and high-throughput analysis of enantiomer composition of these chiral analytes by one chiral AIE molecule.
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http://dx.doi.org/10.1021/acs.joc.6b00371DOI Listing
May 2016

Fluorescence Turn-on Enantioselective Recognition of both Chiral Acidic Compounds and α-Amino Acids by a Chiral Tetraphenylethylene Macrocycle Amine.

J Org Chem 2015 Aug 31;80(16):8096-101. Epub 2015 Jul 31.

Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, People's Republic of China.

New chiral tetraphenylethylene (TPE) macrocycles bearing optically pure amine groups were synthesized and found to have a discriminating ability between the two enantiomers of not only chiral acidic compounds but also α-amino acids by enantioselective aggregation and aggregation-induced emission (AIE) effects. NMR spectra, including 2D-NOESY, disclosed that the host-guest interaction of the macrocycle receptor played a key role in addition to the acid-base interactions.
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http://dx.doi.org/10.1021/acs.joc.5b01194DOI Listing
August 2015

[Standard addition determination of impurities in Na2CrO4 by ICP-AES].

Guang Pu Xue Yu Guang Pu Fen Xi 2015 Feb;35(2):523-6

Coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the trace impurities of Ca, Mg, Al, Fe and Si in industrial sodium chromate. Wavelengths of 167.079, 393.366, 259.940, 279.533 and 251.611 nm were selected as analytical lines for the determination of Al, Ca, Fe, Mg and Si, respectively. The analytical errors can be eliminated by adjusting the determined solution with high pure hydrochloric acid. Standard addition method was used to eliminate matrix effects. The linear correlation, detection limit, precision and recovery for the concerned trace impurities have been examined. The effect of standard addition method on the accuracy for the determination under the selected analytical lines has been studied in detail. The results show that the linear correlations of standard curves were very good (R2 = 0.9988 to 0.9996) under the determined conditions. Detection limits of these trace impurities were in the range of 0.0134 to 0.0280 mg x L(-1). Sample recoveries were within 97.30% to 107.50%, and relative standard deviations were lower than 5.86% for eleven repeated determinations. The detection limits and accuracies established by the experiment can meet the analytical requirements and the analytic procedure was used to determine trace impurities in sodium chromate by ion membrane electrolysis technique successfully. Due to sodium chromate can be changed into sodium dichromate and chromic acid by adding acids, the established method can be further used to monitor trace impurities in these compounds or other hexavalent chromium compounds.
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February 2015

Microtubes and hollow microspheres formed by winding of nanoribbons from self-assembly of tetraphenylethylene amide macrocycles.

Chem Commun (Camb) 2014 Dec;50(96):15212-5

Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

New amide macrocycles based on tetraphenylethylene (TPE) were synthesized. It was found that the TPE amide macrocycles could form microtubes in H2O-THF with 70-80% water by the rolling up of big nanoribbons but produced hollow microspheres in 90% or more water by the winding of thin nanoribbons. The microtubes emitted blue light while the hollow microspheres showed blue-green fluorescence.
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http://dx.doi.org/10.1039/c4cc05390gDOI Listing
December 2014

CH3-π interaction of explosives with cavity of a TPE macrocycle: the key cause for highly selective detection of TNT.

ACS Appl Mater Interfaces 2014 Nov 24;6(22):20067-74. Epub 2014 Oct 24.

Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.

The identification of explosives is critical for analyzing the background of terrorism activities and the origin of pollution aroused by the explosives, but it is a challenge to discriminate the explosives with a very similar structure. Herein we report a series of TPE-based macrocycles with an AIE effect for the 0.2-4 ppb level detection of TNT among a number of nitro-aromatic compounds through fluorescence quenching in natural water sources, whereas the contact mode approach using portable paper sensors exhibited a high sensitivity for the detection of TNT at 1.0 × 10(-13) M level. The reliability of the quantitative analysis has been confirmed by HPLC. Our findings demonstrate that the TPE-based macrocycles have great potential as excellent sensors for TNT. Moreover, it was found for the first time that the macrocycles could selectively recognize nitroaromatics explosives bearing methyl group through a CH3-π interactions, and even exhibit a sole selectivity for TNT among the very difficultly differentiating nitroaromatics including trinitrophenol and trinitrobenzene.
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http://dx.doi.org/10.1021/am505636fDOI Listing
November 2014

Synthesis of tetraphenylethylene pillar[6]arenes and the selective fast quenching of their AIE fluorescence by TNT.

Chem Commun (Camb) 2014 Oct;50(77):11407-10

Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

Tetraphenylethylene pillar[6]arenes with an AIE effect were synthesized for the first time. The fluorescence of the pillar[6]arenes could be quenched much more and much faster by TNT than by other nitroaromatics including 2,4,6-trinitrophenol, which could be used to detect TNT in air.
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http://dx.doi.org/10.1039/c4cc05189kDOI Listing
October 2014

Monomer emission and aggregate emission of an imidazolium macrocycle based on bridged tetraphenylethylene and their quenching by C60.

J Org Chem 2014 Jun 4;79(12):5746-51. Epub 2014 Jun 4.

Key Laboratory for Large-Format Battery Materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.

A novel imidazolium macrocycle based on bridged tetraphenylethylene (TPE) was synthesized. Because it bears the bridged TPE units, this macrocycle not only displays an aggregation-induced emission (AIE) effect but also exhibits monomer emission, which is very rare in AIE compounds. With aggregation of the macrocycle, the aggregate emission increases while the monomer emission decreases. It was found that this imidazolium macrocycle can form a stable 2:1 complex with C60, which gives rise to quenching of both the aggregate emission and the monomer emission. Unexpectedly, the aggregate emission exhibited a higher quenching efficiency than the monomer emission, probably because one adsorbed C60 molecule could affect more macrocycle molecules in the aggregate.
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http://dx.doi.org/10.1021/jo500884zDOI Listing
June 2014

Monomer emission and aggregate emission of TPE derivatives in the presence of γ-cyclodextrin.

Org Lett 2014 Apr 4;16(8):2170-3. Epub 2014 Apr 4.

Key Laboratory for Large-Format Battery materials and System, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.

It was found for the first time that neutral amphiphilc tetraphenylethylene (TPE) derivatives showed an enhanced monomer emission and a decreased aggregate emission when they were included in the cavity of γ-cyclodextrin. This result provided a new insight into the aggregation-induced emission (AIE) effect.
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http://dx.doi.org/10.1021/ol500638cDOI Listing
April 2014

Highly sensitive and selective detection of nitrophenolic explosives by using nanospheres of a tetraphenylethylene macrocycle displaying aggregation-induced emission.

Chemistry 2014 Jan 27;20(1):195-201. Epub 2013 Nov 27.

School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China), Fax: (+86) 27-87543632.

A tetraphenylethylene (TPE) Schiff-base macrocycle showing an aggregation-induced emission (AIE) effect has been synthesized, which could aggregate into nanospheres and emit yellow fluorescence in aqueous media. By virtue of its AIE effect, the macrocycle showed a sensitive and selective response to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP) among a number of nitroaromatic compounds, which could be used to detect TNP and DNP at nanomolar levels. Moreover, it exhibited a superamplified quenching effect with DNP but not with TNP, providing a possible means of discriminating these two compounds. In comparison with open-chain TPE Schiff-bases, the cavity of the macrocycle is essential for the selectivity for DNP over TNP. In addition, quantitative analyses of both DNP and TNP in real water samples and qualitative detection of these two analytes in the solid state by the macrocycle have been tested. The reliability of the quantitative analysis has been confirmed by HPLC. Our findings demonstrate that the TPE Schiff-base macrocycle has great potential as an excellent sensor for DNP and TNP.
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http://dx.doi.org/10.1002/chem.201302638DOI Listing
January 2014

[Determination of major, minor elements in the samples of SrCO3 product by X-ray fluorescence spectrometry].

Guang Pu Xue Yu Guang Pu Fen Xi 2009 Aug;29(8):2268-71

Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, China.

In the present paper a method for the determination of strontium, barium, calcium, magnesium, silicon, iron, aluminum and sulfur in the product of strontium carbonate by X-ray fluorescence spectrometry with pressed powder sample preparation was developed, and the standard samples were synthesized by high purity reagent. As the contents of strontium in the product of strontium carbonate were very high, the phenomenon of spectrum-peak-saturated occurred and the count rate was overflowed according to the measuring condition which was automatically given by the software system of X-ray fluorescence spectrometry. As a result, the deviation of the measurement is greater. According to analyzing the measuring condition of strontium, a method was given for reducing the count rate by reducing the measuring power of strontium, thus achieving the goal of measurement. When sulfate was measured with pressed powder sample, the results were enhanced with the increase in measuring number. In light of this situation, a method was proposed to solve the problem. As the self-forming characteristic of the product of strontium carbonate was not so well, it was very difficult to press the sample successfully. So, the condition of squash method involving the kinds of the adhesives, the mixing technique with powder sample and the pressing-time technique was discussed. During making the sample, it was found that the effects of pellet formation were better if the time could be delayed by 120 seconds. Matrix effect was corrected by alpha coefficient method, the accuracy of the method was evaluated by analysis of synthetic sample. Detection limits of 0.623-107.6 mg x g(-1) were obtained. The results were in good agreement with certified values with precision of < 2.5% RSD.
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August 2009
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