To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparat...To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.展开更多
In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission sp...In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.展开更多
The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic s...The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.展开更多
Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed...Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.展开更多
Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether ...Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.展开更多
Aim Nicotinamide phosphoribosyltransferase （NAMPT） is a promising therapeutic target for cardio-ce- rebrovascular diseases and tumor. Novel NAMPT inhibitors with diverse chemotypes are highly desirable for devel- op...Aim Nicotinamide phosphoribosyltransferase （NAMPT） is a promising therapeutic target for cardio-ce- rebrovascular diseases and tumor. Novel NAMPT inhibitors with diverse chemotypes are highly desirable for devel- opment of therapeutic agents. Methods We carried out a high throughput screening targeting NAMPT on a chemi- cal library of 30000 small-molecules in this study. Assays of NAD levels, anti-proliferative activity, imaging study, RNA interference were conducted in HepG2 cells or primary mouse hepatocytes. Results A non-fluorescent com- pound F671-0003 and a fluorescent compound M049-0244 were found with excellent in vitro activity （IC50：85 nmol · L^-1 and 170 nmol · L^-1 respectively） and anti-proliferative activity against HepG2 cells. These two com- pounds significantly depleted cellular NAD levels. Exogenous NMN rescued their anti-proliferative activity against HepG2 cells. Structure-activity relationship study proposed a binding mode for NAMPT inhibitor F671-0003 and highlighted the importance of hydrogen bonding, hydrophobic and -rr--rr interactions in inhibitor binding. Imaging study provided the evidence that fluorescent compound M049-0244 （3 μmol · L^-1） significantly stained living HepG2 cells. Cellular fluorescence was further verified to be NAMPT dependent by using RNA interference and NAMPT over expression transgenic mice. Conclusions This study provides novel lead compounds and a ＂first-in- class＂ fluorescent probe for imaging NAMPT.展开更多
A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phospho...A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.展开更多
文摘To address the lack of systematic studies on heavy metal fluorescent probes in typical buffer solutions,this study developed a Fe^(3+)and Cu^(2+)fluorescent probe,DHU‑NP‑4,based on a naphthalimide fluorophore.Comparative analysis of the probe's performance in various buffer systems revealed that buffers with high organic content are unsuitable for evaluating such probes.Furthermore,the pH of the solvent system was found to significantly influence the probe's behavior.Under highly acidic conditions(pH≤2),DHU‑NP‑4 exhibited exceptional specificity for Fe^(3+),while in alkaline conditions,it demonstrated high specificity for Cu^(2+).Leveraging these properties,the probe enabled the quantitative detection of Fe^(3+)and Cu^(2+)in solution.
文摘In this study,a self-calibrating near-infrared fluorescence probe was designed and synthesized based on the dual-fluorophore strategy utilizing methylene blue and coumarin.The probe utilized methylene blue(emission spectrum range:640-740 nm)and coumarin fluorophore(emission spectrum range:440-600 nm)as signal output units,thereby achieving effective spectral separation and highly selective detection of HClO.Under physiological pH conditions,HClO triggers an oxidation-cleavage reaction,releasing methylene blue and coumarin,which emit distinct red and green fluorescence,respectively.This dual-emission feature enabled rapid HClO detection with two-channel detection limits of 25.13 nmol·L^(-1)(green channel)and 31.55 nmol·L^(-1)(red channel).Furthermore,in cell imaging experiments,this probe demonstrated excellent cell membrane permeability and low cytotoxicity,successfully enabling the monitoring of both endogenous and exogenous HClO in living cells.By incorporating a twochannel self-calibration system,the probe effectively mitigated signal variations caused by instrumental or environmental interference,substantially improving detection sensitivity and reliability.
文摘The abnormal metabolic activity of the tumor can increase the oxygen consumption in tumor cells,and the poor blood perfusion often happens in tumor regions as well,which are the main reasons that result in a hypoxic situation in the tumor.A fluorescence probe,AQD,with selective response toward hypoxia was designed for the detection of hypoxic tumor cells,which was obtained by the covalent connection of a large planar conjugated fluorophore with good fluorescence stability and a N,N-dimethylaniline moiety via the azo bond.The introduction of the azo bond in AQD caused significant fluorescence emission quenching,and the probe was reduced under hypoxic conditions to release the fluorophore via breaking the azo bond,resulting in the gradual recovery of fluorescence emission.Probe AQD exhibited a remarkable fluorescence response in hypoxic conditions,high selectivity,and good biocompatibility,which was successfully used for the imaging of hypoxic tumor cells and realized the detection of hypoxic A549 cells.
文摘Herein,a luminescent europium-based metal-organic framework(Eu-MOF,[Eu_(3)(L)(HL)(NO_(3))_(2)(DMF)_(2)]·4DMF·5H_(2)O,H_(4)L=5,5′-(pyrazine-2,6-diyl)diisophthalic acid,DMF=N,N-dimethylformamide)was developed for the dual-functional detection of environmental pollutants.This fluorescence-quenching-based sensor exhibited excep-tional sensitivity for both 2,4,6-trinitrophenol(TNP)and tetracycline(TC),achieving remarkably low detection lim-its of 1.96×10^(-6)and 1.71×10^(-7)mol·L^(-1),respectively.Notably,the system exhibited 99%fluorescence quenching ef-ficiency for TC,indicating ultra-efficient analyte recognition.The detection performance surpasses most reported lu-minescent MOF sensors,attributed to synergistic mechanisms of fluorescence resonance energy transfer(FRET)and photoinduced electron transfer(PET).CCDC:2446483.
基金financially supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20241181)the State Key Laboratory of AnalyticalChemistry for Life Science,School of Chemistry and Chemical Engineering,Nanjing University(Grant No.SKLACLS2419)。
文摘Using 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran(TCF)as a near-infrared fluorescent chromophore,we designed and synthesized a TCF-based fluorescent probe TCF-NS by introducing 2,4-dinitrophenyl ether as the recognized site for H_(2)S.The probe TCF-NS displayed a rapid-response fluorescent against H_(2)S with high sensitivity and selection but had no significant fluorescence response to other biothiols.Furthermore,TCF-NS was applied to sense H_(2)S in living cells successfully with minimized cytotoxicity and a large Stokes shift.
文摘Aim Nicotinamide phosphoribosyltransferase （NAMPT） is a promising therapeutic target for cardio-ce- rebrovascular diseases and tumor. Novel NAMPT inhibitors with diverse chemotypes are highly desirable for devel- opment of therapeutic agents. Methods We carried out a high throughput screening targeting NAMPT on a chemi- cal library of 30000 small-molecules in this study. Assays of NAD levels, anti-proliferative activity, imaging study, RNA interference were conducted in HepG2 cells or primary mouse hepatocytes. Results A non-fluorescent com- pound F671-0003 and a fluorescent compound M049-0244 were found with excellent in vitro activity （IC50：85 nmol · L^-1 and 170 nmol · L^-1 respectively） and anti-proliferative activity against HepG2 cells. These two com- pounds significantly depleted cellular NAD levels. Exogenous NMN rescued their anti-proliferative activity against HepG2 cells. Structure-activity relationship study proposed a binding mode for NAMPT inhibitor F671-0003 and highlighted the importance of hydrogen bonding, hydrophobic and -rr--rr interactions in inhibitor binding. Imaging study provided the evidence that fluorescent compound M049-0244 （3 μmol · L^-1） significantly stained living HepG2 cells. Cellular fluorescence was further verified to be NAMPT dependent by using RNA interference and NAMPT over expression transgenic mice. Conclusions This study provides novel lead compounds and a ＂first-in- class＂ fluorescent probe for imaging NAMPT.
文摘A zinc sulfate open framework matrix,[Zn(SO_4)(DMSO)](1),was synthesized by solvothermal evaporationusing dimethyl sulfoxide(DMSO)as the solvent.A compositeP@1,which exhibits fluorescence and room tempera-ture phosphorescence(RTP)properties,was prepared by doping 2,6-naphthalic acid(P)into matrix1at a low con-centration.P@1emitted a green RTP that was visible to the naked eye and lasted for approximately 2 s.P@1exhib-ited selective phosphorescence enhancement response towards Pb^(2+),with a detection limit of 2.52μmol·L^(-1).Themain detection mechanism is the Pb—O coordination-induced phosphorescence enhancement in the system.Inter-estingly,P@1also functioned as a dual-channel probe for the rapid detection of Fe^(3+)ions through fluorescencequenching with a detection limit of 0.038μmol·L^(-1).The recognition mechanism may be attributed to the competi-tive energy absorption betweenP@1and Fe^(3+)ions.CCDC:2388502,1.
