In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especia...In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especially for developing new reaction pathway to afford the functional heterocycle compounds with aggregation-induced emission(AIE)property has been rarely reported.In present work,the multi-site functionalization of in situ generated alkenes with indoles has been developed for the synthesis of diversely functionalized carbazoles through the synergistic construction of multiple C–C bonds and C=O bond.A proposed reaction sequence involving C–H alkenylation/radical oxygen atom transfer/Diels-Alder cycloaddition/dehydrogenative aromatization was supported by experiments and density functional theory calculations.Further derivative carbazole-linked-quinoxaline skeletons represent a class of AIEgens with acceptor-donor-acceptor configuration,which generated the desired twisted intramolecular charge transfer(TICT)AIE properties and could be used as fluorescent probes for detecting the micrometer-sized phase separation of polymer blends.The protocol provides a concise route for the synthesis and application of carbazole-based AIE luminogens.展开更多
It is important to understand the evolution of the matter on the polymer membrane surface.The in situ and real-time monitoring of the membrane surface will not only favor the investigation of selective layer formation...It is important to understand the evolution of the matter on the polymer membrane surface.The in situ and real-time monitoring of the membrane surface will not only favor the investigation of selective layer formation but can also track the fouling process during operation.Herein,an aggregation-induced emission(AIE)-active polymer membrane was prepared by the interfacial polymerization of a cyclodextrin-based glycocluster(CD@Glucose)and a tetraphenylethylene derivative modified with boronic acid groups(TPEDB)on the surface of a polyacrylonitrile(PAN)ultrafiltration membrane.This interfacial polymerization method can be stacked layer-by-layer to regulate the hydrophilicity and pore structure of the membrane.With the increase in the number of polymer layers,the separation and antifouling properties of the membrane gradually improved.Owing to the AIE property of the crosslinking agent TPEDB,the occurrence of interfacial polymerization and the degree of fouling during membrane operation can be monitored by the fluorescence distribution and intensity.With the aggravation of membrane fouling,the fluorescence decreased gradually,but recovered after cleaning.Therefore,this AIE effect can be used for real-time monitoring of interfacial polymerization as well as membrane fouling.展开更多
Aggregation-induced emission(AIE)is a phenomenon characterized by certain fluorescent molecules that exhibit weak or no luminescence in solution but demonstrate significantly enhanced luminescence upon aggregation.Acc...Aggregation-induced emission(AIE)is a phenomenon characterized by certain fluorescent molecules that exhibit weak or no luminescence in solution but demonstrate significantly enhanced luminescence upon aggregation.Accordingly,AIE materials have successfully addressed the limitations associated with aggregation-caused quenching effects and have made significant progress in the application of various fields of medicine in recent years.At present,the application of AIE materials in gastrointestinal(GI)diseases is mainly in GI imaging,diagnosis and treatment.In this review,we summarize the applications of AIE materials in GI pathogens and GI diseases,including inflammatory bowel disease and GI tumors,and outline combined treatment methods of AIE materials in GI tumor therapy.展开更多
Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Tra...Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.展开更多
Photodynamic therapy(PDT)has received much attention in recent years.However,traditional photosensitizers(PSs)applied in PDT usually suffer from aggregation-caused quenching(ACQ)effect in H_(2)O,single and inefficient...Photodynamic therapy(PDT)has received much attention in recent years.However,traditional photosensitizers(PSs)applied in PDT usually suffer from aggregation-caused quenching(ACQ)effect in H_(2)O,single and inefficient photochemical mechanism of action(MoA),poor cancer targeting ability,etc.In this work,two novel Ru(II)-based aggregation-induced emission(AIE)agents(Ru1 and Ru2)were developed.Both complexes exhibited long triplet excited lifetimes and nearly 100%singlet oxygen quantum yields in H_(2)O.In addition,Ru1 and Ru2 displayed potent photo-catalytic reduced nicotinamide adenine dinucleotide(NADH)oxidation activity with turnover frequency(TOF)values of about 1779 and 2000 h^(−1),respectively.Therefore,both Ru1 and Ru2 showed efficient PDT activity towards a series of cancer cells.Moreover,Ru2 was further loaded in bovine serum albumin(BSA)to enhance the tumor targeting ability in vivo,and the obtained Ru2@BSA could selectively accumulate in tumor tissues and effectively inhibit tumor growth on a 4T1 tumor-bearing mouse model.So far as we know,this work represents the first report about Ru(Ⅱ)-)AIE agents that possess high singlet oxygen quantum yields and also potent photocatalytic NADH oxidation activity,and may provide new ideas for rational design of novel PSs with efficient PDT activity.展开更多
Fluorescence imaging-guided photodynamic therapy holds great promise for application in precise cancer diagnosis and treatment,which has motivated high requirements for phototheranostic agents.However,current photosen...Fluorescence imaging-guided photodynamic therapy holds great promise for application in precise cancer diagnosis and treatment,which has motivated high requirements for phototheranostic agents.However,current photosensitizers(PSs)generally face limitations such as short emission wavelength and inadequate reactive oxygen species(ROS)production.Aggregation-caused quenching issue also hinders the phototheranostic efficiency of PSs.Herein,theπ-bridge modulation strategy is proposed to construct ionic PSs with enhanced bioimaging and therapeutic outcomes.Two donor-π-acceptor(D-π-A)molecules TPCPY and TFCPY were obtained by incorporating phenyl and furan units asπ-bridge,respectively.Both PSs feature aggregation-induced near-infrared emission.Under light irradiation,TPCPY and TFCPY can produce both typeⅠandⅡROS.Introducing furan ring in TFCPY enhances the ROS generation capacity by typeⅠphotosensitization process,which is consistent with the reduced energy gap between singlet and triplet states from theoretical calculation.Furthermore,TFCPY can achieve quick cellular uptake,accumulate in mitochondria,and then efficiently kill cancer cells,which is superior to TPCPY.Consequently,TFCPY exhibited good antitumor outcomes and excellent in vivo fluorescence imaging ability.This work provides an efficient molecular engineering of introducing heterocycles into the D-π-A skeleton to develop high-performance PSs with both typeⅠandⅡROS generation.展开更多
Detection of mercury ions(Hg^(2+))in actual samples is of significant importance due to the toxicity of Hg^(2+)to human health.In this work,a simple tetraphenylethene(TPE)derived fluorescent probe TPE-Hg based on aggr...Detection of mercury ions(Hg^(2+))in actual samples is of significant importance due to the toxicity of Hg^(2+)to human health.In this work,a simple tetraphenylethene(TPE)derived fluorescent probe TPE-Hg based on aggregation-induced emission(AIE)mechanism was synthesized.TPE-Hg can visually recognize Hg^(2+)in THF/HEPES(1:9,v/v,HEPES 20 mmol/L,pH 7.3)system with rapid response,strong anti-interference ability,large Stokes shift(203 nm),and low detection limit(7.548×10^(-7)mol/L).The results show that Hg^(2+)triggered elimination of TPE-Hg lead to releasing of an AIE-active compound 2 is responsible to the sensing mechanism.TPE-Hg is applicable to detect Hg^(2+)in actual water samples and image Hg^(2+)in living MCF-7 cells.In addition,TPE-Hg is suitable to assay the Hg^(2+)level in seafood and tea samples,and it is alsoapplicable intest strips.展开更多
Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors ...Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work,a series of mononuclear gold(Ⅰ) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(Ⅰ)-containing complexes. In addition, these phosphors display typical aggregation-induced emission(AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.展开更多
Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced em...Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced emission(AIE) properties become a group of popular luminescent materials recently. The design and synthesis of AIE-active hyperbranched polymers, which combine the advantages of these two types of materials, are attractive but challenging. In this work, four hyperbranched poly(tetrahydropyrimidine)s were synthesized from the metal-free room temperature multicomponent tandem polymerization of diester group-activated internal alkyne,polyfunctional aromatic amines, and formaldehyde in methanol under the catalysis of acetic acid. Through different monomer combination and controlling the monomer loading order, hyperbranched polymers with various topological structures as well as sequences of different functional groups in the polymer backbone were obtained with high molecular weights(up to 3.0 × 10~4 g/mol) in high yields(up to 98%). The hyperbranched poly(tetrahydropyrimidine) emitted faintly in solution, while its luminescence was notably enhanced in the aggregated state, suggesting its typical aggregation-induced emission property. It is anticipated that the multicomponent polymerization may provide a synthetic platform for the construction of hyperbranched polyheterocycles with diverse structures and functionalities.展开更多
Exploring the effective and efficient path of agricultural carbon emission reduction in Henan Province is of great significance to optimizing the strategic layout of China's agricultural emission reduction and car...Exploring the effective and efficient path of agricultural carbon emission reduction in Henan Province is of great significance to optimizing the strategic layout of China's agricultural emission reduction and carbon sequestration.Accordingly,the agricultural carbon emissions of each county were measured scientifically and then the spatial measurement model was utilized to clarify the spatial and temporal evolution trend and spatial effect mechanism of agricultural carbon emissions based on the county data of Henan Province from 2010 to 2020.The results showed that:(1)in 2020,the total agricultural carbon emissions were 134.7274 million tons,with the high distribution in the southeast and low distribution in the northwest;(2)the spatial dependence of agricultural carbon emissions showed a four-stage trend of fluctuating down-continuing up-plummeting-fluctuating up again,and the spatial heterogeneity was dominated by low-low agglomeration,followed by high-low agglomeration;(3)there was an inverted U curve relationship between the level of agricultural economic development and agricultural carbon emissions.The increase in the level of agricultural mechanization and urbanization rate significantly reduced agricultural carbon emissions.The opposite was true for the financial support for agriculture,the income level of rural residents and the structure of the agricultural industry;(4)in terms of spatial spillover effects,the increase in the level of agricultural development in neighbor counties first increased and then decreased agricultural carbon emissions in Henan Province.The mechanization level and urbanization rate of neighbor counties reduced agricultural carbon emissions in Henan Province,and the opposite was true for the income level of rural residents and the scale utilization of agricultural land.展开更多
Large-scale underground projects need accurate in-situ stress information,and the acoustic emission(AE)Kaiser effect method currently offers lower costs and streamlined procedures.In this method,the accuracy and speed...Large-scale underground projects need accurate in-situ stress information,and the acoustic emission(AE)Kaiser effect method currently offers lower costs and streamlined procedures.In this method,the accuracy and speed of Kaiser point identification are important.Thus,this study aims to integrate chaos theory and machine learning for accurately and quickly identifying Kaiser points.An intelligent model of the identification of AE partitioned areas was established by phase space reconstruction(PSR),genetic algorithm(GA),and support vector machine(SVM).Then,the plots of model classification results were made to identify Kaiser points.We refer to this method of identifying Kaiser points as the partitioning plot method based on PSR–GA–SVM(PPPGS).The PSR–GA–SVM model demonstrated outstanding performance,which achieved a 94.37%accuracy rate on the test set,with other evaluation metrics also indicating exceptional performance.The PPPGS identified Kaiser points similar to the tangent-intersection method with greater accuracy.Furthermore,in the feature importance score of the classification model,the fractal dimension extracted by PSR ranked second after accumulated AE count,which confirmed its importance and reliability as a classification feature.The PPPGS was applied to in-situ stress measurement at a phosphate mine in Guizhou Weng'an,China,to validate its practicability,where it demonstrated good performance.展开更多
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...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,^(13)C 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.展开更多
Photodynamic therapy(PDT) employs accumulation of photosensitizers(PSs) in malignant tumor tissue followed by the light-induced generation of cytotoxic reactive oxygen species to kill the tumor cells. The success of P...Photodynamic therapy(PDT) employs accumulation of photosensitizers(PSs) in malignant tumor tissue followed by the light-induced generation of cytotoxic reactive oxygen species to kill the tumor cells. The success of PDT depends on optimal PS dosage that is matched with the ideal power of light. This in turn depends on PS accumulation in target tissue and light administration time and period.As theranostic nanomedicine is driven by multifunctional therapeutics that aim to achieve targeted tissue delivery and image-guided therapy, fluorescent PS nanoparticle(NP)accumulation in target tissues can be ascertained through fluorescence imaging to optimize the light dose and administration parameters. In this regard, zebrafish larvae provide a unique transparent in vivo platform to monitor fluorescent PS bio-distribution and their therapeutic efficiency. Using fluorescent PS NPs with unique aggregation-induced emission characteristics, we demonstrate for the first time the real-time visualization of polymeric NP accumulation in tumor tissue and, more importantly, the best time to conduct PDT using transgenic zebrafish larvae with inducible liver hyperplasia as an example.展开更多
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 varie...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.展开更多
Compared with visible light,near infrared(NIR)light has deeper penetration in biological tisues.Three-photon fuorescence microscopy(3PFM)can effectively utilize the NIR excitation to obtain high-contrast images in the...Compared with visible light,near infrared(NIR)light has deeper penetration in biological tisues.Three-photon fuorescence microscopy(3PFM)can effectively utilize the NIR excitation to obtain high-contrast images in the deep tisue.However,the weak three photon fluorescence signals may be not well presented in the traditional fuorescence intensity imaging mode.Fluorescence lifetime of certain probes is insensitive to the intensity of the excitation laser.Moreover,fluorescence lifetimne imaging microscopy(FLIM)can detect weak signals by utilizing time correlated single photon counting(TCSPC)technique.Thus,it would be an improved strategy to combine the 3PFM imaging with the FLIM together.Herein,DCDPP-2TPA,a novel agegation-induced emission luminogen(AIEgen),was adopted as the fluorescent probes.The three-photon absorption cros-section of the AlEgen,which has a deep-red fluorescence emission,was proved to be large.DCDPP-2TPA nanoparticles were synthesized,and the three photon fluorescence lifetime of which was measured in water.Moreover,in vrivo thre-photon fuorescence lifetime microscopic imaging of a craniotomy mouse was conducted via a home made optical system.High contrast cerebrovascular images of different vertical depths were obtained and the maximun depth was about 600 pumn.Even reaching the depth of 600 pum,tiny capillary vessels as small as 1.9 pum could still be distinguished.The three photon fuorescence lifetimes of the capillaries in some representative images were in accord with that of DCDPP-2TPA nanoparticles in water.A vivid 3D reconstruction was further organized to present a wealth of lifetime information.In the future,the combination strategy of 3PFM and FLIM could be further applied in the brain functional imaging.展开更多
Two functional tetraphenylethylene derivatives modified by vinylpyridine and vinylnitrobenzene,respectively,were synthesized by Heck coupling reaction.Their optical behaviors were investigated.The results showed they ...Two functional tetraphenylethylene derivatives modified by vinylpyridine and vinylnitrobenzene,respectively,were synthesized by Heck coupling reaction.Their optical behaviors were investigated.The results showed they had AIE activity in solution.The property in solid state displayed that both of them had reversible mechanochromism.Upon grinding,their fluorescence spectra showed around 13–40nm red-shift,and could return to the original state after solvent fuming.We believe that this work will be helpful for the design of stimuli-responsive materials in future.展开更多
Stimuli-responsive polymer gels have recently attracted great attention due to their heat/solvent resistance,dimensional stability,and unique sensitivity to external stimuli.In this work,we synthesized thiol-functiona...Stimuli-responsive polymer gels have recently attracted great attention due to their heat/solvent resistance,dimensional stability,and unique sensitivity to external stimuli.In this work,we synthesized thiol-functionalized tetraphenylethylene(TPE)and constructed polymer gels through thiol-ene click reaction.The synthetic process of the polymer gels could be monitored by fluorescence emission of TPE moieties based on aggregation-induced emission mechanism.In addition,due to the dual redox-and acid responsiveness of the polymer gels,in the presence of dithiothreitol and trifluoroacetic acid,fluorescence quenching of the polymer gels can be observed.This stimuli-responsive characteristics endows the polymer gels with potential applications in fluorescent sensing and imaging,cancer diagnosis and selfhealing materials.展开更多
Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities a...Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities and the TPE units to exhibit aggregation-induced emission(AIE)in aqueous solution.These AIE-active nanospheres with cationic feature exhibited selective recognition with fluorescence response for anionic ATP via electrostatic interactions and hydrophobic effects in water.展开更多
The luminescence property of 2,7-diphenyl-fluorenone(DPFO)was previously reported to be very unusual with a large aggregationinduced effect associated with a fluorescence redshift of 150 nm.The phenomenon is reexamine...The luminescence property of 2,7-diphenyl-fluorenone(DPFO)was previously reported to be very unusual with a large aggregationinduced effect associated with a fluorescence redshift of 150 nm.The phenomenon is reexamined in this work.It is found that the abnormal observations are caused by the presence of a trace amount of impurity 2,7-diphenyl-fluorene(DPF)in the as-synthesized DPFO.The pure DPFO molecule does have an intense fluorescence(FL)in solid(528 nm),about 4−5 times larger than in its dilute dichloromethane solutions(542 nm),but with a blueshifted rather than redshifted FL wavelength in solid.The enormous FL enhancement and redshifted FL wavelength of the as-synthesized DPFO solid are due to the presence of impurity DPF.The FL of DPF is much stronger than that of DPFO in dilute solutions and it also has shorter FL wavelengths.In a dilute solution of DPFO with a trace amount of DPF(∼1%),the dominant FL peaks are from DPF.Because the electronic absorption peaks of DPF overlaps with DPFO,the electronic energy of DPF can transfer to DPFO.The energy transfer is faster with the increase of concentration because DPF and surrounding DPFO molecules become closer,which quenches the FL of DPF(356 and 372 nm)and enhances the FL of DPFO(542 nm in solution and 528 nm in solid).Therefore,at high concentrations or in solids,only peak at about 542 or 528 nm shows up,and peaks at 356 and 372 nm disappear.展开更多
Fluorescent vesicles have recently attracted increasing attention because of their potential applications in bioimaging,diagnostics, and theranostics, for example, in vivo study of the delivery and the distribution of...Fluorescent vesicles have recently attracted increasing attention because of their potential applications in bioimaging,diagnostics, and theranostics, for example, in vivo study of the delivery and the distribution of active substances. However, fluorescent vesicles containing conventional organic dyes often suffer from the problem of aggregation-caused quenching(ACQ) of fluorescence.Fluorescent vesicles working with aggregation-induced emission(AIE) offer an extraordinary tool to tackle the ACQ issue, showing advantages such as high emission efficiency, superior photophysical stability, low background interference, and high sensitivity. AIE fluorescent vesicles represent a new type of fluorescent and functional nanomaterials. In this review, we summarize the recent advances in the development of AIE fluorescent vesicles. The review is organized according to the chemical structures and architectures of the amphiphilic molecules that constitute the AIE vesicles, i.e., small-molecule amphiphiles, amphiphilic polymers, and amphiphilic supramolecules and supramacromolecules. The studies on the applications of these AIE vesicles as stimuli-responsive vesicles,fluorescence-guided drug release carriers, cell imaging tools, and fluorescent materials based on fluorescence resonance energy transfer(FRET) are also discussed.展开更多
文摘In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especially for developing new reaction pathway to afford the functional heterocycle compounds with aggregation-induced emission(AIE)property has been rarely reported.In present work,the multi-site functionalization of in situ generated alkenes with indoles has been developed for the synthesis of diversely functionalized carbazoles through the synergistic construction of multiple C–C bonds and C=O bond.A proposed reaction sequence involving C–H alkenylation/radical oxygen atom transfer/Diels-Alder cycloaddition/dehydrogenative aromatization was supported by experiments and density functional theory calculations.Further derivative carbazole-linked-quinoxaline skeletons represent a class of AIEgens with acceptor-donor-acceptor configuration,which generated the desired twisted intramolecular charge transfer(TICT)AIE properties and could be used as fluorescent probes for detecting the micrometer-sized phase separation of polymer blends.The protocol provides a concise route for the synthesis and application of carbazole-based AIE luminogens.
基金supported by the Fundamental Research Funds for Central Universities(No.30922010811).
文摘It is important to understand the evolution of the matter on the polymer membrane surface.The in situ and real-time monitoring of the membrane surface will not only favor the investigation of selective layer formation but can also track the fouling process during operation.Herein,an aggregation-induced emission(AIE)-active polymer membrane was prepared by the interfacial polymerization of a cyclodextrin-based glycocluster(CD@Glucose)and a tetraphenylethylene derivative modified with boronic acid groups(TPEDB)on the surface of a polyacrylonitrile(PAN)ultrafiltration membrane.This interfacial polymerization method can be stacked layer-by-layer to regulate the hydrophilicity and pore structure of the membrane.With the increase in the number of polymer layers,the separation and antifouling properties of the membrane gradually improved.Owing to the AIE property of the crosslinking agent TPEDB,the occurrence of interfacial polymerization and the degree of fouling during membrane operation can be monitored by the fluorescence distribution and intensity.With the aggravation of membrane fouling,the fluorescence decreased gradually,but recovered after cleaning.Therefore,this AIE effect can be used for real-time monitoring of interfacial polymerization as well as membrane fouling.
基金Supported by The Science and Technology Program of Gansu Province,No.23JRRA1015.
文摘Aggregation-induced emission(AIE)is a phenomenon characterized by certain fluorescent molecules that exhibit weak or no luminescence in solution but demonstrate significantly enhanced luminescence upon aggregation.Accordingly,AIE materials have successfully addressed the limitations associated with aggregation-caused quenching effects and have made significant progress in the application of various fields of medicine in recent years.At present,the application of AIE materials in gastrointestinal(GI)diseases is mainly in GI imaging,diagnosis and treatment.In this review,we summarize the applications of AIE materials in GI pathogens and GI diseases,including inflammatory bowel disease and GI tumors,and outline combined treatment methods of AIE materials in GI tumor therapy.
基金support from the National Natural Science Foundation of China(9235630033,22105069)Shanghai Pujiang Program(20PJ1402900)+2 种基金Shanghai Natural Science Foundation(21ZR1418400)Innovation Program of Shanghai Municipal Education Commission(2023FGS01)Natural Science Foundation of Jiangsu Province(BK20231225).
文摘Icing detection is critically important for preventing safety accidents and economic losses,especially concerning ice formation from invalidated anti-icing fluids(water and ethylene glycol)under extreme conditions.Traditional technologies like ultrasonics and capacitor-antenna face challenges with limited detection areas,lower accuracy,and susceptibility to electromagnetic interference.Here,we introduce a novel viscosity-ultrasensitive fluorescent probe 40,4‴-(2,2-diphenyle-thene-1,1-diyl)bis-(3,5-dicarboxylate)(TPE-2B4C)based on AIEgens for moni-toring ice formation of anti-icing fluids in low-temperature environments.TPE-2B4C,consisting of four sodium carboxylate groups and multiple freely rotating benzene rings,demonstrates outstanding solubility in anti-icing fluids and exhibits no fluorescent background signal even at low temperatures(<−20°C).Upon freezing,TPE-2B4C relocates from the water phase to higher viscosity ethylene glycol,causing restriction of benzene rings and a significantly increased green fluorescence signal.TPE-2B4C can successfully determine whether the anti-icing fluids are icing from−5 to−20°C with a high contrast ratio.Due to its simple setup,fast operation,and broad applicability,our new method is anticipated to be employed for rapid,real-time,and large-scale icing detection.
基金supported by National Natural Science Foundation of China(NSFC,No.22371289).
文摘Photodynamic therapy(PDT)has received much attention in recent years.However,traditional photosensitizers(PSs)applied in PDT usually suffer from aggregation-caused quenching(ACQ)effect in H_(2)O,single and inefficient photochemical mechanism of action(MoA),poor cancer targeting ability,etc.In this work,two novel Ru(II)-based aggregation-induced emission(AIE)agents(Ru1 and Ru2)were developed.Both complexes exhibited long triplet excited lifetimes and nearly 100%singlet oxygen quantum yields in H_(2)O.In addition,Ru1 and Ru2 displayed potent photo-catalytic reduced nicotinamide adenine dinucleotide(NADH)oxidation activity with turnover frequency(TOF)values of about 1779 and 2000 h^(−1),respectively.Therefore,both Ru1 and Ru2 showed efficient PDT activity towards a series of cancer cells.Moreover,Ru2 was further loaded in bovine serum albumin(BSA)to enhance the tumor targeting ability in vivo,and the obtained Ru2@BSA could selectively accumulate in tumor tissues and effectively inhibit tumor growth on a 4T1 tumor-bearing mouse model.So far as we know,this work represents the first report about Ru(Ⅱ)-)AIE agents that possess high singlet oxygen quantum yields and also potent photocatalytic NADH oxidation activity,and may provide new ideas for rational design of novel PSs with efficient PDT activity.
基金supported by the funding from Natural Science Foundation of Jilin Province(No.20220101191JC)National Natural Science Foundation of China(No.22175033)the 13th Five-Year Program for Science and Technology of Education Department of Jilin Province(No.JJKH20230800KJ)。
文摘Fluorescence imaging-guided photodynamic therapy holds great promise for application in precise cancer diagnosis and treatment,which has motivated high requirements for phototheranostic agents.However,current photosensitizers(PSs)generally face limitations such as short emission wavelength and inadequate reactive oxygen species(ROS)production.Aggregation-caused quenching issue also hinders the phototheranostic efficiency of PSs.Herein,theπ-bridge modulation strategy is proposed to construct ionic PSs with enhanced bioimaging and therapeutic outcomes.Two donor-π-acceptor(D-π-A)molecules TPCPY and TFCPY were obtained by incorporating phenyl and furan units asπ-bridge,respectively.Both PSs feature aggregation-induced near-infrared emission.Under light irradiation,TPCPY and TFCPY can produce both typeⅠandⅡROS.Introducing furan ring in TFCPY enhances the ROS generation capacity by typeⅠphotosensitization process,which is consistent with the reduced energy gap between singlet and triplet states from theoretical calculation.Furthermore,TFCPY can achieve quick cellular uptake,accumulate in mitochondria,and then efficiently kill cancer cells,which is superior to TPCPY.Consequently,TFCPY exhibited good antitumor outcomes and excellent in vivo fluorescence imaging ability.This work provides an efficient molecular engineering of introducing heterocycles into the D-π-A skeleton to develop high-performance PSs with both typeⅠandⅡROS generation.
基金funded by the National Natural Science Foundation of China(Nos.22278038,21878023),the Program for Distinguished Professor of Liaoning Province.
文摘Detection of mercury ions(Hg^(2+))in actual samples is of significant importance due to the toxicity of Hg^(2+)to human health.In this work,a simple tetraphenylethene(TPE)derived fluorescent probe TPE-Hg based on aggregation-induced emission(AIE)mechanism was synthesized.TPE-Hg can visually recognize Hg^(2+)in THF/HEPES(1:9,v/v,HEPES 20 mmol/L,pH 7.3)system with rapid response,strong anti-interference ability,large Stokes shift(203 nm),and low detection limit(7.548×10^(-7)mol/L).The results show that Hg^(2+)triggered elimination of TPE-Hg lead to releasing of an AIE-active compound 2 is responsible to the sensing mechanism.TPE-Hg is applicable to detect Hg^(2+)in actual water samples and image Hg^(2+)in living MCF-7 cells.In addition,TPE-Hg is suitable to assay the Hg^(2+)level in seafood and tea samples,and it is alsoapplicable intest strips.
基金support from the National Natural Science Foundation of China(Nos.22175069,22061018,21702079 and 21772054)the 111 Project(No.B17019),the Natural Science Foundation for Distinguished Young Scholars of Jiangxi Province(No.20212ACB213003)the Academic and Technical Leader Plan of Jiangxi Provincial Main Disciplines(No.20212BCJ23004).
文摘Developing phosphors with long-lifetime(millisecond scale or even longer) solid state room temperature phosphorescence(RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work,a series of mononuclear gold(Ⅰ) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(Ⅰ)-containing complexes. In addition, these phosphors display typical aggregation-induced emission(AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.
基金financially supported by the National Natural Science Foundation of China (Nos. 21822102, 21774034, 21490573, 21490574, and 21788102)the Natural Science Foundation of Guangdong Province (Nos. 2016A030306045 and 2016030312002)the Innovation and Technology Commission of Hong Kong (No. ITC-CNERC14SC01)
文摘Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced emission(AIE) properties become a group of popular luminescent materials recently. The design and synthesis of AIE-active hyperbranched polymers, which combine the advantages of these two types of materials, are attractive but challenging. In this work, four hyperbranched poly(tetrahydropyrimidine)s were synthesized from the metal-free room temperature multicomponent tandem polymerization of diester group-activated internal alkyne,polyfunctional aromatic amines, and formaldehyde in methanol under the catalysis of acetic acid. Through different monomer combination and controlling the monomer loading order, hyperbranched polymers with various topological structures as well as sequences of different functional groups in the polymer backbone were obtained with high molecular weights(up to 3.0 × 10~4 g/mol) in high yields(up to 98%). The hyperbranched poly(tetrahydropyrimidine) emitted faintly in solution, while its luminescence was notably enhanced in the aggregated state, suggesting its typical aggregation-induced emission property. It is anticipated that the multicomponent polymerization may provide a synthetic platform for the construction of hyperbranched polyheterocycles with diverse structures and functionalities.
基金Supported by the Humanities and Social Sciences Planning Program of the Ministry of Education(23YJA790027)。
文摘Exploring the effective and efficient path of agricultural carbon emission reduction in Henan Province is of great significance to optimizing the strategic layout of China's agricultural emission reduction and carbon sequestration.Accordingly,the agricultural carbon emissions of each county were measured scientifically and then the spatial measurement model was utilized to clarify the spatial and temporal evolution trend and spatial effect mechanism of agricultural carbon emissions based on the county data of Henan Province from 2010 to 2020.The results showed that:(1)in 2020,the total agricultural carbon emissions were 134.7274 million tons,with the high distribution in the southeast and low distribution in the northwest;(2)the spatial dependence of agricultural carbon emissions showed a four-stage trend of fluctuating down-continuing up-plummeting-fluctuating up again,and the spatial heterogeneity was dominated by low-low agglomeration,followed by high-low agglomeration;(3)there was an inverted U curve relationship between the level of agricultural economic development and agricultural carbon emissions.The increase in the level of agricultural mechanization and urbanization rate significantly reduced agricultural carbon emissions.The opposite was true for the financial support for agriculture,the income level of rural residents and the structure of the agricultural industry;(4)in terms of spatial spillover effects,the increase in the level of agricultural development in neighbor counties first increased and then decreased agricultural carbon emissions in Henan Province.The mechanization level and urbanization rate of neighbor counties reduced agricultural carbon emissions in Henan Province,and the opposite was true for the income level of rural residents and the scale utilization of agricultural land.
基金financially supported by the National Natural Science Foundation of China(Nos.52374107 and 52304165)。
文摘Large-scale underground projects need accurate in-situ stress information,and the acoustic emission(AE)Kaiser effect method currently offers lower costs and streamlined procedures.In this method,the accuracy and speed of Kaiser point identification are important.Thus,this study aims to integrate chaos theory and machine learning for accurately and quickly identifying Kaiser points.An intelligent model of the identification of AE partitioned areas was established by phase space reconstruction(PSR),genetic algorithm(GA),and support vector machine(SVM).Then,the plots of model classification results were made to identify Kaiser points.We refer to this method of identifying Kaiser points as the partitioning plot method based on PSR–GA–SVM(PPPGS).The PSR–GA–SVM model demonstrated outstanding performance,which achieved a 94.37%accuracy rate on the test set,with other evaluation metrics also indicating exceptional performance.The PPPGS identified Kaiser points similar to the tangent-intersection method with greater accuracy.Furthermore,in the feature importance score of the classification model,the fractal dimension extracted by PSR ranked second after accumulated AE count,which confirmed its importance and reliability as a classification feature.The PPPGS was applied to in-situ stress measurement at a phosphate mine in Guizhou Weng'an,China,to validate its practicability,where it demonstrated good performance.
基金financially supported by the National Natural Science Foundation of China(Nos.21878136,21372194 and 21773103)。
文摘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,^(13)C 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.
基金financial support from National Research Foundation Investigatorship (R279-000-444-281)National University of Singapore (R279-000-482-133)
文摘Photodynamic therapy(PDT) employs accumulation of photosensitizers(PSs) in malignant tumor tissue followed by the light-induced generation of cytotoxic reactive oxygen species to kill the tumor cells. The success of PDT depends on optimal PS dosage that is matched with the ideal power of light. This in turn depends on PS accumulation in target tissue and light administration time and period.As theranostic nanomedicine is driven by multifunctional therapeutics that aim to achieve targeted tissue delivery and image-guided therapy, fluorescent PS nanoparticle(NP)accumulation in target tissues can be ascertained through fluorescence imaging to optimize the light dose and administration parameters. In this regard, zebrafish larvae provide a unique transparent in vivo platform to monitor fluorescent PS bio-distribution and their therapeutic efficiency. Using fluorescent PS NPs with unique aggregation-induced emission characteristics, we demonstrate for the first time the real-time visualization of polymeric NP accumulation in tumor tissue and, more importantly, the best time to conduct PDT using transgenic zebrafish larvae with inducible liver hyperplasia as an example.
基金financially supported by the National Basic Research Program(No.2015CB931801)the National Natural Science Foundation of China(Nos.21204049 and 51473093)
文摘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.
基金supported by National Natural Science Foundation of China(61735016)Zhejiang Provincial Natural Science Foundation of China(LR17F050001).
文摘Compared with visible light,near infrared(NIR)light has deeper penetration in biological tisues.Three-photon fuorescence microscopy(3PFM)can effectively utilize the NIR excitation to obtain high-contrast images in the deep tisue.However,the weak three photon fluorescence signals may be not well presented in the traditional fuorescence intensity imaging mode.Fluorescence lifetime of certain probes is insensitive to the intensity of the excitation laser.Moreover,fluorescence lifetimne imaging microscopy(FLIM)can detect weak signals by utilizing time correlated single photon counting(TCSPC)technique.Thus,it would be an improved strategy to combine the 3PFM imaging with the FLIM together.Herein,DCDPP-2TPA,a novel agegation-induced emission luminogen(AIEgen),was adopted as the fluorescent probes.The three-photon absorption cros-section of the AlEgen,which has a deep-red fluorescence emission,was proved to be large.DCDPP-2TPA nanoparticles were synthesized,and the three photon fluorescence lifetime of which was measured in water.Moreover,in vrivo thre-photon fuorescence lifetime microscopic imaging of a craniotomy mouse was conducted via a home made optical system.High contrast cerebrovascular images of different vertical depths were obtained and the maximun depth was about 600 pumn.Even reaching the depth of 600 pum,tiny capillary vessels as small as 1.9 pum could still be distinguished.The three photon fuorescence lifetimes of the capillaries in some representative images were in accord with that of DCDPP-2TPA nanoparticles in water.A vivid 3D reconstruction was further organized to present a wealth of lifetime information.In the future,the combination strategy of 3PFM and FLIM could be further applied in the brain functional imaging.
基金financially supported by the National Natural Science Foundation of China(Nos.21676113,21402057,21772054)Distinguished Young Scholar of Hubei Province(No.2018CFA079)+5 种基金Youth Chen-Guang Project of Wuhan(No.2016070204010098)the 111 Project(No.B17019)the Ministry-Province Jointly Constructed Base for State Key Lab-Shenzhen Key Laboratory of Chemical Biology(Shenzhen),the State Key Laboratory of Materials-Oriented Chemical Engineering(No.KL17-10)the Open Project Fund of Key Laboratory of Natural Resources of Changbai Mountain&Functional Molecules,Yanbian University,Ministry of Education(No.NRFM201701)the Foundation of Key Laboratory of Synthetic and Biological Colloids,Jiangnan University,Ministry of Education(No.JDSJ2017-07)Self-determined Research Funds of CCNU from the Colleges’Basic Research and Operation of MOE(No.CCNU18TS012)
文摘Two functional tetraphenylethylene derivatives modified by vinylpyridine and vinylnitrobenzene,respectively,were synthesized by Heck coupling reaction.Their optical behaviors were investigated.The results showed they had AIE activity in solution.The property in solid state displayed that both of them had reversible mechanochromism.Upon grinding,their fluorescence spectra showed around 13–40nm red-shift,and could return to the original state after solvent fuming.We believe that this work will be helpful for the design of stimuli-responsive materials in future.
基金supported by the National Natural Science Foundation of China (No.51773190 and No.51973206)。
文摘Stimuli-responsive polymer gels have recently attracted great attention due to their heat/solvent resistance,dimensional stability,and unique sensitivity to external stimuli.In this work,we synthesized thiol-functionalized tetraphenylethylene(TPE)and constructed polymer gels through thiol-ene click reaction.The synthetic process of the polymer gels could be monitored by fluorescence emission of TPE moieties based on aggregation-induced emission mechanism.In addition,due to the dual redox-and acid responsiveness of the polymer gels,in the presence of dithiothreitol and trifluoroacetic acid,fluorescence quenching of the polymer gels can be observed.This stimuli-responsive characteristics endows the polymer gels with potential applications in fluorescent sensing and imaging,cancer diagnosis and selfhealing materials.
基金supported by the National Natural Science Foundation of China(Nos.21971208 and 21771145)the Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China(No.2021JC-37)the Fok Ying Tong Education Foundation(No.171010).
文摘Functional dicyclophanes with various substituents(e.g.,NO_(2),Br,OCH_(3)and OH)were synthesized via one-pot S_(N)2 reaction.Dicyclophanes can form nanospheres via the head-to-tail self-assembly between the cavities and the TPE units to exhibit aggregation-induced emission(AIE)in aqueous solution.These AIE-active nanospheres with cationic feature exhibited selective recognition with fluorescence response for anionic ATP via electrostatic interactions and hydrophobic effects in water.
基金supported by the National Natural Science Foundation of China(No.21627805,No.21673004,No.21804004,and No.21821004)Ministry of Science and Technology of China(No.2017YFA0204702)。
文摘The luminescence property of 2,7-diphenyl-fluorenone(DPFO)was previously reported to be very unusual with a large aggregationinduced effect associated with a fluorescence redshift of 150 nm.The phenomenon is reexamined in this work.It is found that the abnormal observations are caused by the presence of a trace amount of impurity 2,7-diphenyl-fluorene(DPF)in the as-synthesized DPFO.The pure DPFO molecule does have an intense fluorescence(FL)in solid(528 nm),about 4−5 times larger than in its dilute dichloromethane solutions(542 nm),but with a blueshifted rather than redshifted FL wavelength in solid.The enormous FL enhancement and redshifted FL wavelength of the as-synthesized DPFO solid are due to the presence of impurity DPF.The FL of DPF is much stronger than that of DPFO in dilute solutions and it also has shorter FL wavelengths.In a dilute solution of DPFO with a trace amount of DPF(∼1%),the dominant FL peaks are from DPF.Because the electronic absorption peaks of DPF overlaps with DPFO,the electronic energy of DPF can transfer to DPFO.The energy transfer is faster with the increase of concentration because DPF and surrounding DPFO molecules become closer,which quenches the FL of DPF(356 and 372 nm)and enhances the FL of DPFO(542 nm in solution and 528 nm in solid).Therefore,at high concentrations or in solids,only peak at about 542 or 528 nm shows up,and peaks at 356 and 372 nm disappear.
基金financially supported by the French National Research Agency (No. ANR-16-CE29-0028)the National Natural Science Foundation of China (Nos. 21604001 and 21528402)
文摘Fluorescent vesicles have recently attracted increasing attention because of their potential applications in bioimaging,diagnostics, and theranostics, for example, in vivo study of the delivery and the distribution of active substances. However, fluorescent vesicles containing conventional organic dyes often suffer from the problem of aggregation-caused quenching(ACQ) of fluorescence.Fluorescent vesicles working with aggregation-induced emission(AIE) offer an extraordinary tool to tackle the ACQ issue, showing advantages such as high emission efficiency, superior photophysical stability, low background interference, and high sensitivity. AIE fluorescent vesicles represent a new type of fluorescent and functional nanomaterials. In this review, we summarize the recent advances in the development of AIE fluorescent vesicles. The review is organized according to the chemical structures and architectures of the amphiphilic molecules that constitute the AIE vesicles, i.e., small-molecule amphiphiles, amphiphilic polymers, and amphiphilic supramolecules and supramacromolecules. The studies on the applications of these AIE vesicles as stimuli-responsive vesicles,fluorescence-guided drug release carriers, cell imaging tools, and fluorescent materials based on fluorescence resonance energy transfer(FRET) are also discussed.
