The assembling of a coating of time-resolved fluorescent chelator BSPDA （ abbreviated for 4, 7-bis （ sulfhydrylphenyl）-1, 10-phenanthroline-2, 9-dicarboxylic acid） onto a nano-gold layer was demonstrated. First, B...The assembling of a coating of time-resolved fluorescent chelator BSPDA （ abbreviated for 4, 7-bis （ sulfhydrylphenyl）-1, 10-phenanthroline-2, 9-dicarboxylic acid） onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion （Ⅲ, Eu^3＋ ） was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3＋ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating＇s specific complexation with Eu^3＋ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3＋ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3＋ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing （or labeling） processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices.展开更多
[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PP...[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PPR.[Methods]Soluble N protein and NH fusion protein were successfully obtained in an Escherichia coli expression system by optimizing E.coli codon and expression conditions.Furthermore,based on purified soluble N protein and NH fusion protein,a double-antigen sandwich time-resolved fluorescence immunoassay method for detection of peste des petits ruminants virus(PPRV)was established.[Results]The method has high sensitivity and specificity and can specifically detect the antibody against PPRV in sheep serum,and it has no cross reaction with other related diseases.The method was used to detect 292 clinical samples,and compared with French IDVET competition ELISA kit.The coincidence rates of positive samples and negative samples from the two kinds of test kits were 92.47%and 97.26%,respectively,and the overall coincidence rate was 94.86%.The intra-group and inter-group coefficients of variation in the repeatability test were less than 10%.[Conclusions]Compared with the traditional ELISA method,the double-antigen sandwich time-resolved fluorescence immunoassay for detection of PPRV has equivalent sensitivity and specificity,and simple and rapid operation,and thus high application and popularization value.展开更多
Timefluorescence decays were first performed on hematoporphyrin derivative laser No.3 in buffer at different micelles concentration.The flu.orescence lifetime constants,measured with a time-correlated single photon co...Timefluorescence decays were first performed on hematoporphyrin derivative laser No.3 in buffer at different micelles concentration.The flu.orescence lifetime constants,measured with a time-correlated single photon counting system;could be fitted by two or three exponential components with different relative peak amplitudes depending on the observation wavelength^thus indicating the presence of different emitting molecular species and/or of molecular species in different aggregational states.展开更多
Using a picosecond excitation source and a time-resolved streak camera detection system,the time-resolved fluorescence spectra of purified C_(60) have been recorded from toluene solution at room temperature.A fluoresc...Using a picosecond excitation source and a time-resolved streak camera detection system,the time-resolved fluorescence spectra of purified C_(60) have been recorded from toluene solution at room temperature.A fluorescence peak at about 730nm was detected and its lifetime was directly determined to be 1.1±0.1 ns.Two fluorescence peaks obtained from the mixture of C_(60) and C_(70) at 676 and 696nm were mainly related to C_(70) content.展开更多
Accurate quantification of interleukin-6(IL6),a biomarker central to sepsis and cytokine release syndrome,is essential for assessing disease severity.Here,we present a high-performance lateral flow assay(LFA)that leve...Accurate quantification of interleukin-6(IL6),a biomarker central to sepsis and cytokine release syndrome,is essential for assessing disease severity.Here,we present a high-performance lateral flow assay(LFA)that leverages a novel conjugate:europium nanoparticles(EuNPs)labels linked via tetrahedral DNA frameworks(TDFs).The TDF precisely controls antibody orientation,minimizes nonspecific binding,and improves conjugate stability.Combined with the strong,time-resolved fluorescence of EuNPs,this design achieves a broad dynamic range and preserves linearity at high analyte concentrations.The platform quantitatively detects IL6 from 0 to 5000 pg/mL within 10 min,showing excellent agreement with reference methods.This DNA-nanostructureenhanced approach provides a robust and portable point-of-care testing strategy for critical clinical decisionmaking.展开更多
An enhancement method of rapid lifetime determination is proposed for time-resolved fluorescence imaging to discriminate substances with approximate fluorescence lifetime in forensic examination. In the method, an ima...An enhancement method of rapid lifetime determination is proposed for time-resolved fluorescence imaging to discriminate substances with approximate fluorescence lifetime in forensic examination. In the method, an image-exclusive-OR treatment with filter threshold adaptively chosen is presented to extract the region of interest from dual-gated fluorescence intensity images, and then the fluorescence lifetime image is reconstructed based on the rapid lifetime determination algorithm. Furthermore, a maximum and minimum threshold filtering is developed to automatically realize visualization enhancement of the lifetime image. In proof experiments, compared with traditional fluorescence intensity imaging and rapid lifetime determination method, the proposed method automatically distinguishes altered and obliterated documents written by two brands of highlighters with the same color and close fluorescence lifetime.展开更多
While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these fe...While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.展开更多
Cyclo[n]Thiophenes(CnTs)are a distinctive class ofπ-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics.However,the devel...Cyclo[n]Thiophenes(CnTs)are a distinctive class ofπ-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics.However,the development of CnTs has been largely impeded by inefficient synthetic route.In this work,we employ a bridge strategy using bipyridine as bridge to link two quaterthiophene units resulting in-shaped bicyclosystem.This strain-retaining approach improves the synthesis efficiency of the macrocycles.Two new macrocyclic molecules,(4T-2hexyl-2Me)_(2)-DPBP and(4T-2hexyl)_(2)-DPBP,were successfully synthesized in total yield 17%and 16%,respectively.Single-crystal structure of(4T-2hexyl-2Me)_(2)-DPBP reveals that the bipyridine bridge is orthogonally strapped by two quaterthiophene units.Notably,both compounds exhibit aggregation-induced emission enhancement(AIEE)behavior-an unprecedented feature among CnT-based macrocycles.Theoretical calculations reveal that this AIE phenomenon originates from the restriction of intramolecular motion(RIM)in the aggregated state,which suppresses the non-radiative decay channels.These results demonstrate a generalized strategy for the synthesis of functionalπ-conjugated macrocyclic molecules based fluorescent materials.展开更多
Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves ...Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves targeting superficial tumors in patients with macronodular cirrhosis and an irregular liver surface.In a minimally invasive setting,the lack of tactile feedback on the hepatic surface makes detecting subcapsular HCC with ultrasound alone challenging.ICG fusion images can mimic the tactile feedback of the hand and act as an ultrasound booster.ICG fluorescence can be used to evaluate tumor residues after minimally invasive thermal ablation.ICG fluorescence imaging can also be used to identify the grade of HCC early on and evaluate the microinvasive component.展开更多
The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we develope...The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we developed in vivo second near-infrared(NIR-II)window fluorescence(FL)and ratiometric photoacoustic(RPA)dual-modality imaging of GSH using a GSH-activatable probe(LET-14).LET-14 was synthesized based on a rhodamine hybrid xanthene skeleton with a FL shielding 2,4-dinitrobenzene sulfonyl group that can be specifically cleaved by GSH,thus resulting in a markedly bathochromic-shift absorption,a 6.5-fold increase in NIR-II FL intensity(FL920)and a 13-fold increase in RPA signal(PA880/PA705)in vitro.Intriguingly,LET-14 exhibits good selectivity and sensitivity for NIR-II FL and RPA dual-modality imaging of GSH in 4T1 tumor-bearing mouse model.Our findings develop an in vivo detection tool of GSH,which has great potential in the field of cancer diagnosis.展开更多
Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon ...Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon peaking and neutrality.However,its complex terrain,fragile ecosystem,and variable climate challenge carbon sink stability.Vegetation phenology significantly impacts carbon absorption and release,making accurate phenological data essential for understanding carbon sequestration dynamics.The widespread distribution of evergreen forests and their weak seasonal variation in canopy introduce significant uncertainties in extracting phenology using traditional remote sensing information in this region.These limitations can lead to inaccurate assessments of carbon sink dynamics.Therefore,precise phenology extraction and analysis are vital for improving ecosystem dynamics and the carbon cycle in Southwest China.Firstly,we employed different ways to evaluate the ability of solar-induced chlorophyll fluorescence(SIF)and traditional remote sensing information to extract phenology.Secondly,based on SIF,we analyzed the spatial and temporal changes in the start of the growing season(SOS),the end of the growing season(EOS),and the length of the growing season(LOS)from 2001 to 2020.Finally,we systematically analyzed the response of SOS and EOS to five preseason climatic factors.The results showed that(1)SIF outperformed traditional remote sensing information in extracting phenology.(2)Vegetation phenology exhibited significant spatial heterogeneity.Moreover,SOS,EOS,and LOS showed trends of advancement,delay,and extension both overall and across all vegetation types.(3)Precipitation was the main factor influencing SOS,while surface downward solar radiation and mean temperature were the main factors affecting EOS,and the phenology of different vegetation types showed a great difference in response to preseason climate factors.These findings improve our understanding of vegetation phenology and its dynamics over Southwest China.展开更多
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc...A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.展开更多
Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application p...Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application potential in information encryption,anti-counterfeiting,but remained challenging in improving the security.Herein,we described a self-erased time-resolved information encryption via using photoswitchable dual-color fluorescent polymeric nanoparticles(PDFPNs)containing two fluorescence dyes(blue and red)and photochromic spiroxazine derivatives.In view of the different thermo-induced isomerization rates of photochromic spiroxazine derivatives in different flexible substrates,the decoloration rate of PDFPNs can be programmatically tuned by regulating ratio between rigid polymer and flexible polymer.Therefore,after ultraviolet light(UV)irradiation,correct information could only be recognized in preestablished time during the self-erased process.Our results indicated that PDFPNs exhibited fast photo-responsibility(2 min),high fluorescence contrast,well-pleasing photo-reversibility(>20 times),and programmable thermo-responsiveness(24 s-6 h).We thus demonstrated their application in the selferased time-resolved information encryption and anti-counterfeiting with high security.展开更多
Very recently,we have proposed that all culprit molecules of arteriosclerosis mightpossess a common and measurable inherent property,namely,a coaggregating ten-dency.Extensive kinetic measurements of these tendencies ...Very recently,we have proposed that all culprit molecules of arteriosclerosis mightpossess a common and measurable inherent property,namely,a coaggregating ten-dency.Extensive kinetic measurements of these tendencies in terms of △CAgC valueshave led to a new and surprising observation,i.e.,the cholesteryl ester with a longsaturated 18-carbon chain(CE-18)actually has a much smaller tendency towardcoaggregation than that of the ester with a“short”8-carbon chain(CE-8).Thisstate of affairs has been coined as the“chain-foldability effect”,i.e.,the 18-carbon展开更多
IN a previous paper, we have studied the energy transfer mechanism among the PBS-thy-lakoid complex in detail by using steady-state spectra and deconvolution techniques. The ex-perimental results indicated that the en...IN a previous paper, we have studied the energy transfer mechanism among the PBS-thy-lakoid complex in detail by using steady-state spectra and deconvolution techniques. The ex-perimental results indicated that the energy transfer from PBS to two reaction centers of PS Ⅰand PS Ⅱ were parallel, and confirmed the model which was suggested by Mullineaxu.展开更多
Ⅰ. INTRODUCTIONPhotodynamic therapy (PDT) which utilizes hematoporphyrin derivative (HpD) as a photosensitizing drug has increasingly being used for the local treatment of malignant tumors. The success of this method...Ⅰ. INTRODUCTIONPhotodynamic therapy (PDT) which utilizes hematoporphyrin derivative (HpD) as a photosensitizing drug has increasingly being used for the local treatment of malignant tumors. The success of this method is attributed to the ability of HpD to accumulate to展开更多
Triple exciplex formed between polyacenaphthalene and terephthalic dimethylester (TDE) has been studied by means of the steady-state and time-resolved fluorescence spectra. The theoretical model of the triple exciplex...Triple exciplex formed between polyacenaphthalene and terephthalic dimethylester (TDE) has been studied by means of the steady-state and time-resolved fluorescence spectra. The theoretical model of the triple exciplex formation for a flexible polymer chain in a dilute solution has been proposed. The fluorescence decays of the monomer, the exciplex and the triple exciplex obey a double exponential rule in the pbotophysical processes of the triple exciplex formation. The association rate constant of the exciplex formation is k_3=6.0×10~9s^(-1)(mol/L)^(-1); the association rate constant of the triple exciplex formation is k_6=5.2×10~7s^(-1). A mechanism for the triple exciplex formation from the exciplex to the triple exciplex has been proved through the noncrystal films corresponding to the same concentrations of the solution systems and the fluorescence lifetimes of the intramolecular excimer.展开更多
An intramolecular excimer of poly(2- vinyl) naphthalene was formed by non-adjacentchromophores interaction, then a triple exciplex was formed by interaction with the acceptormolecule further in dilute solution. The li...An intramolecular excimer of poly(2- vinyl) naphthalene was formed by non-adjacentchromophores interaction, then a triple exciplex was formed by interaction with the acceptormolecule further in dilute solution. The lifetime of the intramolecular excimer of poly(2-vinyl) naphthalene, τ_2 = 18.83 ns and the rate constant for the triple exciplex formation,k_7 = 4. 18× 10~9 (mol/L)^(-1)s^(-1), under diffusion-control were measured. An excimer or anexciplex could be an intermediate of the triple exciplex formation. A theoretical model ofthe triple exciplex formation is proposed.展开更多
Nanoparticle labes conjuaged with biomolecules have been used in a variety of different assay application.We investigated the possibility of using europium(Ⅲ)chated-doped silica nanoparticle conjugated with streptavi...Nanoparticle labes conjuaged with biomolecules have been used in a variety of different assay application.We investigated the possibility of using europium(Ⅲ)chated-doped silica nanoparticle conjugated with streptavidin(SA)to detect mouse IgG by time-resolved fluorescence immunoassay(TRFIA).Results demonstrate that the nanoparticle is a novel kind of superior fluourscent probe which could be effectively applied in time-resolved fluorescent immunoassay with high detective sensitivity.In the present study,the lowest detection limit of mouse IgG is 34 pg mL^(-1).展开更多
Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti...Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.展开更多
基金Project supported by the National Natural Science Foundation of China (20505020) the Natural Science Foundation ofGuangdong Province (06300086) +2 种基金 China Postdoctoral Science Foundation (20060390202) Scientific Research Fund ofHunan Provincial Education Department (05C508) Skeleton Youth Faculty Programof Hunan Higher Educational School
文摘The assembling of a coating of time-resolved fluorescent chelator BSPDA （ abbreviated for 4, 7-bis （ sulfhydrylphenyl）-1, 10-phenanthroline-2, 9-dicarboxylic acid） onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion （Ⅲ, Eu^3＋ ） was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3＋ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating＇s specific complexation with Eu^3＋ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3＋ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3＋ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing （or labeling） processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices.
基金Supported by National Key R&D Program for the Prevention and Control of Major Exotic Animal Diseases(2022YFD1800500)National Mutton Sheep Industrial Technology System(CARS39)+2 种基金Key Research and Development Program of Shandong Province(Major Science and Technology Innovation Project)(2021CXGC011306)Scientific Research Project of General Administration of Customs(2024HK033)Scientific Research Project of Jinan Customs(2023JK005).
文摘[Objectives]This study was conducted to explore rapid and large-scale screening and detection of peste des petits ruminants(PPR),so as to provide important technical means for prevention,control and purification of PPR.[Methods]Soluble N protein and NH fusion protein were successfully obtained in an Escherichia coli expression system by optimizing E.coli codon and expression conditions.Furthermore,based on purified soluble N protein and NH fusion protein,a double-antigen sandwich time-resolved fluorescence immunoassay method for detection of peste des petits ruminants virus(PPRV)was established.[Results]The method has high sensitivity and specificity and can specifically detect the antibody against PPRV in sheep serum,and it has no cross reaction with other related diseases.The method was used to detect 292 clinical samples,and compared with French IDVET competition ELISA kit.The coincidence rates of positive samples and negative samples from the two kinds of test kits were 92.47%and 97.26%,respectively,and the overall coincidence rate was 94.86%.The intra-group and inter-group coefficients of variation in the repeatability test were less than 10%.[Conclusions]Compared with the traditional ELISA method,the double-antigen sandwich time-resolved fluorescence immunoassay for detection of PPRV has equivalent sensitivity and specificity,and simple and rapid operation,and thus high application and popularization value.
文摘Timefluorescence decays were first performed on hematoporphyrin derivative laser No.3 in buffer at different micelles concentration.The flu.orescence lifetime constants,measured with a time-correlated single photon counting system;could be fitted by two or three exponential components with different relative peak amplitudes depending on the observation wavelength^thus indicating the presence of different emitting molecular species and/or of molecular species in different aggregational states.
文摘Using a picosecond excitation source and a time-resolved streak camera detection system,the time-resolved fluorescence spectra of purified C_(60) have been recorded from toluene solution at room temperature.A fluorescence peak at about 730nm was detected and its lifetime was directly determined to be 1.1±0.1 ns.Two fluorescence peaks obtained from the mixture of C_(60) and C_(70) at 676 and 696nm were mainly related to C_(70) content.
基金supported by National Key R&D Program of China(2022YFF0710000)National Natural Science Foundation of China(22461142140)Shanghai Jiao Tong University 2030 Initiative。
文摘Accurate quantification of interleukin-6(IL6),a biomarker central to sepsis and cytokine release syndrome,is essential for assessing disease severity.Here,we present a high-performance lateral flow assay(LFA)that leverages a novel conjugate:europium nanoparticles(EuNPs)labels linked via tetrahedral DNA frameworks(TDFs).The TDF precisely controls antibody orientation,minimizes nonspecific binding,and improves conjugate stability.Combined with the strong,time-resolved fluorescence of EuNPs,this design achieves a broad dynamic range and preserves linearity at high analyte concentrations.The platform quantitatively detects IL6 from 0 to 5000 pg/mL within 10 min,showing excellent agreement with reference methods.This DNA-nanostructureenhanced approach provides a robust and portable point-of-care testing strategy for critical clinical decisionmaking.
基金supported by the National Natural Science Foundation of China (NSFC) (No. U1736101)the Youth Innovation Promotion Association CAS (No. 2017155)。
文摘An enhancement method of rapid lifetime determination is proposed for time-resolved fluorescence imaging to discriminate substances with approximate fluorescence lifetime in forensic examination. In the method, an image-exclusive-OR treatment with filter threshold adaptively chosen is presented to extract the region of interest from dual-gated fluorescence intensity images, and then the fluorescence lifetime image is reconstructed based on the rapid lifetime determination algorithm. Furthermore, a maximum and minimum threshold filtering is developed to automatically realize visualization enhancement of the lifetime image. In proof experiments, compared with traditional fluorescence intensity imaging and rapid lifetime determination method, the proposed method automatically distinguishes altered and obliterated documents written by two brands of highlighters with the same color and close fluorescence lifetime.
基金supported by the National Natural Science Foundation of China(22025503,22220102004,22401093)the Science and Technology Commission of Shanghai Municipality(24DX1400200)+2 种基金the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD40)the Programme of Introducing Talents of Discipline to Universities(B16017)the China Postdoctoral Science Foundation(2023M741167,GZB20230211,2024T170273)。
文摘While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.
基金support from the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0520000)the National Key R&D Program of China(No.2022YFA1203200)+3 种基金National Natural Science Foundation of China(No.52273170)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2021030)Postdoctoral Fellowship Program of CPSF(No.GZC20232735)BMS Junior Fellow of Beijing National Laboratory For molecular Science(No.2023BMS20111).
文摘Cyclo[n]Thiophenes(CnTs)are a distinctive class ofπ-conjugated macrocyclic molecules that have attracted growing attention owing to their structural aesthetics and organic electronic characteristics.However,the development of CnTs has been largely impeded by inefficient synthetic route.In this work,we employ a bridge strategy using bipyridine as bridge to link two quaterthiophene units resulting in-shaped bicyclosystem.This strain-retaining approach improves the synthesis efficiency of the macrocycles.Two new macrocyclic molecules,(4T-2hexyl-2Me)_(2)-DPBP and(4T-2hexyl)_(2)-DPBP,were successfully synthesized in total yield 17%and 16%,respectively.Single-crystal structure of(4T-2hexyl-2Me)_(2)-DPBP reveals that the bipyridine bridge is orthogonally strapped by two quaterthiophene units.Notably,both compounds exhibit aggregation-induced emission enhancement(AIEE)behavior-an unprecedented feature among CnT-based macrocycles.Theoretical calculations reveal that this AIE phenomenon originates from the restriction of intramolecular motion(RIM)in the aggregated state,which suppresses the non-radiative decay channels.These results demonstrate a generalized strategy for the synthesis of functionalπ-conjugated macrocyclic molecules based fluorescent materials.
文摘Over the past ten years,numerous papers have been published on the use of indocyanine green(ICG)fluorescence in liver surgery for hepatocellular carcinoma(HCC).There are many different applications.The first involves targeting superficial tumors in patients with macronodular cirrhosis and an irregular liver surface.In a minimally invasive setting,the lack of tactile feedback on the hepatic surface makes detecting subcapsular HCC with ultrasound alone challenging.ICG fusion images can mimic the tactile feedback of the hand and act as an ultrasound booster.ICG fluorescence can be used to evaluate tumor residues after minimally invasive thermal ablation.ICG fluorescence imaging can also be used to identify the grade of HCC early on and evaluate the microinvasive component.
基金supported by the National Natural Science Foundation of China(Nos.82372116,U23A2097)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515010620)+2 种基金Shenzhen Medical Research Fund(Nos.B2302047,A2302047)Shenzhen Science and Technology Program(No.JCYJ20220818095806014)Research Team Cultivation Program of Shenzhen University(No.2023QNT019).
文摘The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we developed in vivo second near-infrared(NIR-II)window fluorescence(FL)and ratiometric photoacoustic(RPA)dual-modality imaging of GSH using a GSH-activatable probe(LET-14).LET-14 was synthesized based on a rhodamine hybrid xanthene skeleton with a FL shielding 2,4-dinitrobenzene sulfonyl group that can be specifically cleaved by GSH,thus resulting in a markedly bathochromic-shift absorption,a 6.5-fold increase in NIR-II FL intensity(FL920)and a 13-fold increase in RPA signal(PA880/PA705)in vitro.Intriguingly,LET-14 exhibits good selectivity and sensitivity for NIR-II FL and RPA dual-modality imaging of GSH in 4T1 tumor-bearing mouse model.Our findings develop an in vivo detection tool of GSH,which has great potential in the field of cancer diagnosis.
基金supported by the National Natural Science Foundation of China[Grant NO.42401465 and 42401464]Yunnan Fundamental Research Projects[Grant NO.202501AT070343,202401AU070169 and 202401CF070161]+1 种基金Natural Science Fund of Kunming University of Science and Technology(KKZ3202421125)Yunnan Provincial Talent Project“High-level Talent Training Support Plan”[YNWR-QNBJ-2020-031]。
文摘Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon peaking and neutrality.However,its complex terrain,fragile ecosystem,and variable climate challenge carbon sink stability.Vegetation phenology significantly impacts carbon absorption and release,making accurate phenological data essential for understanding carbon sequestration dynamics.The widespread distribution of evergreen forests and their weak seasonal variation in canopy introduce significant uncertainties in extracting phenology using traditional remote sensing information in this region.These limitations can lead to inaccurate assessments of carbon sink dynamics.Therefore,precise phenology extraction and analysis are vital for improving ecosystem dynamics and the carbon cycle in Southwest China.Firstly,we employed different ways to evaluate the ability of solar-induced chlorophyll fluorescence(SIF)and traditional remote sensing information to extract phenology.Secondly,based on SIF,we analyzed the spatial and temporal changes in the start of the growing season(SOS),the end of the growing season(EOS),and the length of the growing season(LOS)from 2001 to 2020.Finally,we systematically analyzed the response of SOS and EOS to five preseason climatic factors.The results showed that(1)SIF outperformed traditional remote sensing information in extracting phenology.(2)Vegetation phenology exhibited significant spatial heterogeneity.Moreover,SOS,EOS,and LOS showed trends of advancement,delay,and extension both overall and across all vegetation types.(3)Precipitation was the main factor influencing SOS,while surface downward solar radiation and mean temperature were the main factors affecting EOS,and the phenology of different vegetation types showed a great difference in response to preseason climate factors.These findings improve our understanding of vegetation phenology and its dynamics over Southwest China.
文摘A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.
基金financially supported by the National Key R&D Program of China(Nos.2023YFB3812400,2023YFB3812403)National Natural Foundation of China(Nos.52273206,52350233)+1 种基金Hunan Provincial Natural Science Foundation(No.2021JJ10029)Huxiang High-level Talent Gathering Project(No.2022RC4039).
文摘Photoswitchable fluorescent polymeric nanoparticles were widely concerned because of their excellent features including the flexible design,easy preparation and functionalization,and thus exhibited great application potential in information encryption,anti-counterfeiting,but remained challenging in improving the security.Herein,we described a self-erased time-resolved information encryption via using photoswitchable dual-color fluorescent polymeric nanoparticles(PDFPNs)containing two fluorescence dyes(blue and red)and photochromic spiroxazine derivatives.In view of the different thermo-induced isomerization rates of photochromic spiroxazine derivatives in different flexible substrates,the decoloration rate of PDFPNs can be programmatically tuned by regulating ratio between rigid polymer and flexible polymer.Therefore,after ultraviolet light(UV)irradiation,correct information could only be recognized in preestablished time during the self-erased process.Our results indicated that PDFPNs exhibited fast photo-responsibility(2 min),high fluorescence contrast,well-pleasing photo-reversibility(>20 times),and programmable thermo-responsiveness(24 s-6 h).We thus demonstrated their application in the selferased time-resolved information encryption and anti-counterfeiting with high security.
基金the National Natural Science Foundation of China Laboratory of Photochemistry and PhotophysicsInstitute of Photographic Chemistry,Chinese Academy of Sciences.
文摘Very recently,we have proposed that all culprit molecules of arteriosclerosis mightpossess a common and measurable inherent property,namely,a coaggregating ten-dency.Extensive kinetic measurements of these tendencies in terms of △CAgC valueshave led to a new and surprising observation,i.e.,the cholesteryl ester with a longsaturated 18-carbon chain(CE-18)actually has a much smaller tendency towardcoaggregation than that of the ester with a“short”8-carbon chain(CE-8).Thisstate of affairs has been coined as the“chain-foldability effect”,i.e.,the 18-carbon
文摘IN a previous paper, we have studied the energy transfer mechanism among the PBS-thy-lakoid complex in detail by using steady-state spectra and deconvolution techniques. The ex-perimental results indicated that the energy transfer from PBS to two reaction centers of PS Ⅰand PS Ⅱ were parallel, and confirmed the model which was suggested by Mullineaxu.
文摘Ⅰ. INTRODUCTIONPhotodynamic therapy (PDT) which utilizes hematoporphyrin derivative (HpD) as a photosensitizing drug has increasingly being used for the local treatment of malignant tumors. The success of this method is attributed to the ability of HpD to accumulate to
基金Project supported by the National Natural Science Foundation of China.
文摘Triple exciplex formed between polyacenaphthalene and terephthalic dimethylester (TDE) has been studied by means of the steady-state and time-resolved fluorescence spectra. The theoretical model of the triple exciplex formation for a flexible polymer chain in a dilute solution has been proposed. The fluorescence decays of the monomer, the exciplex and the triple exciplex obey a double exponential rule in the pbotophysical processes of the triple exciplex formation. The association rate constant of the exciplex formation is k_3=6.0×10~9s^(-1)(mol/L)^(-1); the association rate constant of the triple exciplex formation is k_6=5.2×10~7s^(-1). A mechanism for the triple exciplex formation from the exciplex to the triple exciplex has been proved through the noncrystal films corresponding to the same concentrations of the solution systems and the fluorescence lifetimes of the intramolecular excimer.
文摘An intramolecular excimer of poly(2- vinyl) naphthalene was formed by non-adjacentchromophores interaction, then a triple exciplex was formed by interaction with the acceptormolecule further in dilute solution. The lifetime of the intramolecular excimer of poly(2-vinyl) naphthalene, τ_2 = 18.83 ns and the rate constant for the triple exciplex formation,k_7 = 4. 18× 10~9 (mol/L)^(-1)s^(-1), under diffusion-control were measured. An excimer or anexciplex could be an intermediate of the triple exciplex formation. A theoretical model ofthe triple exciplex formation is proposed.
基金the National 973 Program(No.2010CB933901)Shanghai Leading Academic Discipline Project(No.S30109)+1 种基金Shanghai Pujing ProgramShanghai Nano Program(No.0752nm024)is gratefully acknowlegded.
文摘Nanoparticle labes conjuaged with biomolecules have been used in a variety of different assay application.We investigated the possibility of using europium(Ⅲ)chated-doped silica nanoparticle conjugated with streptavidin(SA)to detect mouse IgG by time-resolved fluorescence immunoassay(TRFIA).Results demonstrate that the nanoparticle is a novel kind of superior fluourscent probe which could be effectively applied in time-resolved fluorescent immunoassay with high detective sensitivity.In the present study,the lowest detection limit of mouse IgG is 34 pg mL^(-1).
文摘Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.
