Cell-selective fluorescent probes have emerged as essential tools for live-cell imaging,enabling the differentiation of specific cell types within complex biological systems.Unlike traditional antibody-based methods t...Cell-selective fluorescent probes have emerged as essential tools for live-cell imaging,enabling the differentiation of specific cell types within complex biological systems.Unlike traditional antibody-based methods that target extracellular proteins,small-molecule probes can access intracellular environments and exploit diverse biochemical features for selective retention or activation.This perspective categorizes the mechanisms of cell selectivity into five principal strategies:Protein-oriented,carbohydrate-oriented,lipid-oriented,gating-oriented,and metabolism-oriented live-cell distinctions.Each class capitalizes on a unique cellular trait ranging from protein expression and membrane composition to transporter activity and metabolic enzyme presence.We discuss representative examples of each mechanism,outline a decision-tree workflow for elucidating a new probe's mode of action,and highlight how understanding these mechanisms is critical for both basic biological research and therapeutic probe design.Looking ahead,the development of such mechanism-informed cell-specific probes holds promise for advancing precision cell targeting in biomedical applications.展开更多
Schizophrenia(SCZ) is a severe mental disorder with an unclear pathogenesis.Increasing evidence suggests that oxidative stress(OS) may contribute to the neuropathological processes underlying SCZ.Biothiols,key endogen...Schizophrenia(SCZ) is a severe mental disorder with an unclear pathogenesis.Increasing evidence suggests that oxidative stress(OS) may contribute to the neuropathological processes underlying SCZ.Biothiols,key endogenous antioxidants,have been proposed as potential biomarkers for the disease.However,due to the presence of the blood-brain barrier(BBB),fluorescent probes are rarely used to image biothiols in the brain of SCZ models.In this study,a series of fluorescent probes for biothiols were developed using dicyanoisophorone derivatives as fluorophores known for their excellent optical properties,and carboxylic esters as recognition units.A parallel synthesis and rapid screening strategy was employed to construct and optimize these probes.By introducing trifluoromethyl and benzothiazole groups into the fluorophore,the emission wavelength was successfully shifted into the near-infrared region.Additionally,various trifluoromethyl-substituted aromatic and nitrogen heterocyclic compounds were incorporated to optimize the carboxylic esters,thereby improving the probes' reactivity and lipophilicity.Systematic evaluation of the physicochemical characteristics,and optical performance led to the identification of DCIBT-11 as the most promising candidate.DCI-BT-11 demonstrated excellent BBB permeability and a good response to biothiols both in vitro and in vivo.Notably,DCI-BT-11 was used for the first time to visualize biothiol flux and assess the therapeutic effects of the antioxidant N-acetylcysteine(NAC) in the brains of SCZ mouse models,offering new insights into the role of OS in the pathogenesis and treatment of SCZ.展开更多
Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of...Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of multiple RSSs significant for evaluating ferroptosis therapy.However,the traditional techniques,including fluorescent(FL) imaging and electrospray ionization-based mass spectrometry(MS) detection,cannot achieve the discrimination of different RSSs.Herein,simultaneous MS detection of multiple RSSs,including cysteine(Cys),homocysteine(Hcy),glutathione(GSH) and hydrogen sulfide(H_(2)S),was obtained upon enhancing ionization efficiency by a fluorescent probe(NBD-O-1).Based on the interaction between NBD-O-1 and RSSs,the complex of RSSs with a fragment of NBD-O-1 can be generated,which can be easily ionized for MS detection in the negative mode.Therefore,the intracellular RSSs can be well detected upon the incubation of He La cells with the probe of NBD-O-1,exhibiting the total RSS levels by the FL imaging and further providing expression of each RSS by enhanced MS detection.Furthermore,the RSSs during ferroptosis in He La cells have been evaluated using the present strategy,demonstrating the potential for ferroptosis examinations.This work has made an unconventional application of a fluorescent probe to enhance the detection of multiple RSSs by MS,providing significant molecular information for addressing the ferroptosis mechanism.展开更多
The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensit...The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensity changes,which can compromise accuracy and repeatability.In this study,we report a novel fluorescent probe(R)-Z1 that achieves effective enantioselective recognition of chiral amino acids in water by altering emission wavelengths(>60 nm).This water-soluble probe(R)-Z1 exhibits cyan or yellow-green luminescence upon interaction with amino acid enantiomers,enabling reliable chiral detection of 14 natural amino acids.It also allows for the determination of enantiomeric excess through monitoring changes in luminescent color.Additionally,a logic operation with two inputs and three outputs was constructed based on these optical properties.Notably,amino acid enantiomers were successfully detected via dual-channel analysis at both the food and cellular levels.This study provides a new dynamic luminescence-based tool for the accurate sensing and detection of amino acid enantiomers.展开更多
To address the challenge of low survival rates and limited data collection efficiency in current virtual probe deployments,which results from anomaly detection mechanisms in location-based service(LBS)applications,thi...To address the challenge of low survival rates and limited data collection efficiency in current virtual probe deployments,which results from anomaly detection mechanisms in location-based service(LBS)applications,this paper proposes a novel virtual probe deployment method based on user behavioral feature analysis.The core idea is to circumvent LBS anomaly detection by mimicking real-user behavior patterns.First,we design an automated data extraction algorithm that recognizes graphical user interface(GUI)elements to collect spatio-temporal behavior data.Then,by analyzing the automatically collected user data,we identify normal users’spatio-temporal patterns and extract their features such as high-activity time windows and spatial clustering characteristics.Subsequently,an antidetection scheduling strategy is developed,integrating spatial clustering optimization,load-balanced allocation,and time window control to generate probe scheduling schemes.Additionally,a self-correction mechanism based on an exponential backoff strategy is implemented to rectify anomalous behaviors andmaintain system stability.Experiments in real-world environments demonstrate that the proposed method significantly outperforms baseline methods in terms of both probe ban rate and task completion rate,while maintaining high time efficiency.This study provides a more reliable and clandestine solution for geosocial data collection and lays the foundation for building more robust virtual probe systems.展开更多
Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the q...Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the quality of these medicinal materials and contributing to various health issues.Due to a lack of effective monitoring and imaging tools,the physiological effects of excessive SO_(2) residues in traditional Chinese medicine remain unclear.Therefore,developing a rapid and effective tool for detecting SO_(2) is crucial for understanding its metabolic pathways and effects in vivo.In this study,we developed a near infrared(NIR) and ratiometric fluorescent probe,NIR-RS,which exhibits high sensitivity,selectivity,and rapid response for SO_(2) detection.Notably,NIR-RS accurately quantifies SO_(2) contents in Pinelliae rhizoma(P.rhizoma) samples,with recovery rates from 98.46 % to 102.40 %,and relative standard deviations(RSDs)< 5.0 %.For bioimaging applications,NIR-RS has low cytotoxicity and good mitochondrial-targeting ability,making it suitable for imaging exogenous and endogenous SO_(2) in mitochondria.Additionally,NIR-RS was successfully applied to image SO_(2) content of P.rhizoma samples within cells,revealing that high SO_(2) residue elevated mitochondria adenosine triphosphate(ATP) content,these findings reveal that P.rhizoma with excessive SO_(2) can affect the organism's growth mechanisms through alterations in ATP pathways.In vivo,SO_(2) was found to predominantly accumulate in the liver following gavage with P.rhizoma solution,with accumulation levels increasing in proportion to SO_(2) residue concentration.High SO_(2) concentrations in P.rhizoma can cause pulmonary fibrosis and gastric mucosal damage.This work provides a valuable tool for regulating SO_(2) content in P.rhizoma and may help researcher better understand the metabolism of SO_(2) derivatives and explore their physiological roles in biological systems.展开更多
The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further impr...The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.展开更多
Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with ...Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with the decrease in welding heat input,the weld surface is smoother.The Ti/Al joint interface is flat without obvious Ti and Al mixed structure,and the hook structure is not formed under optimal parameters.Due to the enhanced breaking effect of the stirring head,the hook structural defects and intermetallic compounds are more likely to form at the Ti/Al interface at high rotational speed of 1000 r/min,thereby deteriorating the mechanical properties of joints.Decreasing the heat input is beneficial to hardness enhancement of the aluminum alloy in the weld nugget zone.Under the optimal parameters of rotation speed of 800 r/min and welding speed of 120 mm/min,the maximum tensile shear strength of joint is 289 N/mm.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
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
Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint def...Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.展开更多
Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a seri...Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.展开更多
The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optic...The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optical microscope,scanning electron microscope,tensile test at room temperature,corrosion immersion tests and electrochemical measurements.The results show that the introduction of TIG arc during FSW process results in a more uniform microstructure of the joint with no tunnel hole defects.Furthermore,it enhances tensile strength and elongation of the joint with increased rates of 11.5%and 50.0%,respectively;meanwhile,the corrosion current density and largest corrosion depth are decreased with reduction rates of 78.2%and 45.7%,respectively.TIG-FSW can promote flow,contact and diffusion of materials,thus improving microstructure of the joint.Additionally,it reduces the size and number of secondary phase particles.Consequently,these factors contribute to the higher tensile properties and corrosion resistance of the joints.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
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
This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwel...This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.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
A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 ...A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 and the transformation into strongly fluorescent aldehyde C1.Probe C2 could recognize Cu^(2+)through a marked fluorescence enhancement with the detection limit as low as 150 nmol/L.By virtue of this unique catalytic hydrolysis reaction,compound C2 displayed highly selective response toward Cu^(2+)over other common ions even in the presence of excessive competitive ions.Furthermore,there was a good linear relationship between the intensity change and the concentration of Cu^(2+)ions,which was beneficial for the exactly quantitative detection.Especially,the efficient detection of Cu^(2+)with C2 for the practical application was successfully performed in gas-generating agents detection.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
基金supported by the Starting growth Technological R&D Program(TIPS Program,RS-2024-00468327)funded by the Ministry of SMEs and Startups(MSS,Korea)in 2024 and National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(Nos.2023R1A2C300453411 and RS2024-00411069),Glocal University 30 project(Molecular Imaging Center,POSTECH).
文摘Cell-selective fluorescent probes have emerged as essential tools for live-cell imaging,enabling the differentiation of specific cell types within complex biological systems.Unlike traditional antibody-based methods that target extracellular proteins,small-molecule probes can access intracellular environments and exploit diverse biochemical features for selective retention or activation.This perspective categorizes the mechanisms of cell selectivity into five principal strategies:Protein-oriented,carbohydrate-oriented,lipid-oriented,gating-oriented,and metabolism-oriented live-cell distinctions.Each class capitalizes on a unique cellular trait ranging from protein expression and membrane composition to transporter activity and metabolic enzyme presence.We discuss representative examples of each mechanism,outline a decision-tree workflow for elucidating a new probe's mode of action,and highlight how understanding these mechanisms is critical for both basic biological research and therapeutic probe design.Looking ahead,the development of such mechanism-informed cell-specific probes holds promise for advancing precision cell targeting in biomedical applications.
基金supported by the National Natural Science Foundation of China (Nos.22177025,21807021,22177026)the Science Fund for Creative Research Groups of the Natural Science Foundation of Hebei Province (No.B2021201038)+1 种基金the Foundation of Hebei University (No.050001-513300201004)the Director’s Foundation of the Key Laboratory of Medicinal Chemistry and Molecular Diagnosis,Ministry of Education,Hebei University (No.MCMDZR2024003)。
文摘Schizophrenia(SCZ) is a severe mental disorder with an unclear pathogenesis.Increasing evidence suggests that oxidative stress(OS) may contribute to the neuropathological processes underlying SCZ.Biothiols,key endogenous antioxidants,have been proposed as potential biomarkers for the disease.However,due to the presence of the blood-brain barrier(BBB),fluorescent probes are rarely used to image biothiols in the brain of SCZ models.In this study,a series of fluorescent probes for biothiols were developed using dicyanoisophorone derivatives as fluorophores known for their excellent optical properties,and carboxylic esters as recognition units.A parallel synthesis and rapid screening strategy was employed to construct and optimize these probes.By introducing trifluoromethyl and benzothiazole groups into the fluorophore,the emission wavelength was successfully shifted into the near-infrared region.Additionally,various trifluoromethyl-substituted aromatic and nitrogen heterocyclic compounds were incorporated to optimize the carboxylic esters,thereby improving the probes' reactivity and lipophilicity.Systematic evaluation of the physicochemical characteristics,and optical performance led to the identification of DCIBT-11 as the most promising candidate.DCI-BT-11 demonstrated excellent BBB permeability and a good response to biothiols both in vitro and in vivo.Notably,DCI-BT-11 was used for the first time to visualize biothiol flux and assess the therapeutic effects of the antioxidant N-acetylcysteine(NAC) in the brains of SCZ mouse models,offering new insights into the role of OS in the pathogenesis and treatment of SCZ.
基金supported by the National Key Research and Development Program of China (No.2024YFA1509600)National Natural Science Foundation of China (Nos.22474010 and 22274012)the Fundamental Research Funds for the Central Universities (No.2233300007)。
文摘Ferroptosis has exhibited great potential in therapies and intracellular reducing agents of sulfur species(RSSs) in the thiol-dependent redox systems are crucial in ferroptosis.This makes the simultaneous detection of multiple RSSs significant for evaluating ferroptosis therapy.However,the traditional techniques,including fluorescent(FL) imaging and electrospray ionization-based mass spectrometry(MS) detection,cannot achieve the discrimination of different RSSs.Herein,simultaneous MS detection of multiple RSSs,including cysteine(Cys),homocysteine(Hcy),glutathione(GSH) and hydrogen sulfide(H_(2)S),was obtained upon enhancing ionization efficiency by a fluorescent probe(NBD-O-1).Based on the interaction between NBD-O-1 and RSSs,the complex of RSSs with a fragment of NBD-O-1 can be generated,which can be easily ionized for MS detection in the negative mode.Therefore,the intracellular RSSs can be well detected upon the incubation of He La cells with the probe of NBD-O-1,exhibiting the total RSS levels by the FL imaging and further providing expression of each RSS by enhanced MS detection.Furthermore,the RSSs during ferroptosis in He La cells have been evaluated using the present strategy,demonstrating the potential for ferroptosis examinations.This work has made an unconventional application of a fluorescent probe to enhance the detection of multiple RSSs by MS,providing significant molecular information for addressing the ferroptosis mechanism.
基金the financial support from the National Natural Science Foundation of China(Nos.22377097,22307036,22074114)Natural Science Foundation of Hubei Province of China(Nos.2020CFB623,2021CFB556)Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education(No.LCX202305)。
文摘The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensity changes,which can compromise accuracy and repeatability.In this study,we report a novel fluorescent probe(R)-Z1 that achieves effective enantioselective recognition of chiral amino acids in water by altering emission wavelengths(>60 nm).This water-soluble probe(R)-Z1 exhibits cyan or yellow-green luminescence upon interaction with amino acid enantiomers,enabling reliable chiral detection of 14 natural amino acids.It also allows for the determination of enantiomeric excess through monitoring changes in luminescent color.Additionally,a logic operation with two inputs and three outputs was constructed based on these optical properties.Notably,amino acid enantiomers were successfully detected via dual-channel analysis at both the food and cellular levels.This study provides a new dynamic luminescence-based tool for the accurate sensing and detection of amino acid enantiomers.
基金supported by theNationalNatural Science Foundation of China(No.U23A20305)National Key Research and Development Program of China(No.2022YFB3102900)+1 种基金Innovation Scientists and Technicians Troop Construction Projects of Henan Province,China(No.254000510007)Key Research and Development Project of Henan Province(No.221111321200).
文摘To address the challenge of low survival rates and limited data collection efficiency in current virtual probe deployments,which results from anomaly detection mechanisms in location-based service(LBS)applications,this paper proposes a novel virtual probe deployment method based on user behavioral feature analysis.The core idea is to circumvent LBS anomaly detection by mimicking real-user behavior patterns.First,we design an automated data extraction algorithm that recognizes graphical user interface(GUI)elements to collect spatio-temporal behavior data.Then,by analyzing the automatically collected user data,we identify normal users’spatio-temporal patterns and extract their features such as high-activity time windows and spatial clustering characteristics.Subsequently,an antidetection scheduling strategy is developed,integrating spatial clustering optimization,load-balanced allocation,and time window control to generate probe scheduling schemes.Additionally,a self-correction mechanism based on an exponential backoff strategy is implemented to rectify anomalous behaviors andmaintain system stability.Experiments in real-world environments demonstrate that the proposed method significantly outperforms baseline methods in terms of both probe ban rate and task completion rate,while maintaining high time efficiency.This study provides a more reliable and clandestine solution for geosocial data collection and lays the foundation for building more robust virtual probe systems.
基金supported by the Natural Science Foundation of Hubei Province (Nos.2023AFB376 and 2024AFD287)National Key Research and Development Program (No.2023YFC3503804)the National Natural Science Foundation of China (No.22077044)。
文摘Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the quality of these medicinal materials and contributing to various health issues.Due to a lack of effective monitoring and imaging tools,the physiological effects of excessive SO_(2) residues in traditional Chinese medicine remain unclear.Therefore,developing a rapid and effective tool for detecting SO_(2) is crucial for understanding its metabolic pathways and effects in vivo.In this study,we developed a near infrared(NIR) and ratiometric fluorescent probe,NIR-RS,which exhibits high sensitivity,selectivity,and rapid response for SO_(2) detection.Notably,NIR-RS accurately quantifies SO_(2) contents in Pinelliae rhizoma(P.rhizoma) samples,with recovery rates from 98.46 % to 102.40 %,and relative standard deviations(RSDs)< 5.0 %.For bioimaging applications,NIR-RS has low cytotoxicity and good mitochondrial-targeting ability,making it suitable for imaging exogenous and endogenous SO_(2) in mitochondria.Additionally,NIR-RS was successfully applied to image SO_(2) content of P.rhizoma samples within cells,revealing that high SO_(2) residue elevated mitochondria adenosine triphosphate(ATP) content,these findings reveal that P.rhizoma with excessive SO_(2) can affect the organism's growth mechanisms through alterations in ATP pathways.In vivo,SO_(2) was found to predominantly accumulate in the liver following gavage with P.rhizoma solution,with accumulation levels increasing in proportion to SO_(2) residue concentration.High SO_(2) concentrations in P.rhizoma can cause pulmonary fibrosis and gastric mucosal damage.This work provides a valuable tool for regulating SO_(2) content in P.rhizoma and may help researcher better understand the metabolism of SO_(2) derivatives and explore their physiological roles in biological systems.
基金supported by the National Natural Science Foundation of China(Grant No.52035005)the Key R&D Program of Shandong Province in China(Grant No.2021ZLGX01).
文摘The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%.
基金National Natural Science Foundation of China(52275349)Key Research and Development Program of Shandong Province(2021ZLGX01)。
文摘Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with the decrease in welding heat input,the weld surface is smoother.The Ti/Al joint interface is flat without obvious Ti and Al mixed structure,and the hook structure is not formed under optimal parameters.Due to the enhanced breaking effect of the stirring head,the hook structural defects and intermetallic compounds are more likely to form at the Ti/Al interface at high rotational speed of 1000 r/min,thereby deteriorating the mechanical properties of joints.Decreasing the heat input is beneficial to hardness enhancement of the aluminum alloy in the weld nugget zone.Under the optimal parameters of rotation speed of 800 r/min and welding speed of 120 mm/min,the maximum tensile shear strength of joint is 289 N/mm.
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.
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.
基金the National Natural Science Foundation of China(Nos.22325703,22377071,U23A6009)Research Project Supported by Shanxi Scholarship Council of China(No.2022-002)+1 种基金the Shanxi Province Science Foundation(No.202203021221009)Shanxi Province Science and Technology activities for overseas people selected funding project(No.2024001)。
文摘Rheumatoid arthritis(RA) is a chronic inflammatory disease with multi-system damage and autoimmune features.The main clinical manifestations of RA include joint pain,swelling,and stiffness,and RA may lead to joint deformity and dysfunction in severe cases.The pathologic development of RA involves complex interactions of multiple biomarkers,and detecting a single biomarker may produce falsepositive results due to other confounding factors.Therefore,fluorescent probes that can detect multiple biomarkers simultaneously are crucial for precise RA diagnosis.Peroxynitrite(ONOO^(-)) and viscosity are inflammation-related factors in cells.In this study,we developed a dual responsive near-infrared fluorescent probe,YLS,for ONOO^(-) and viscosity.The probe features dual-channel turn-on fluorescence responses at 625 and 760 nm upon the presence of ONOO^(-) and viscosity,respectively.Supported by YLS,we found that during RA pathology,lymphocyte infiltration not only increases the concentration of proteins in the joint fluid resulting in elevated viscosity;at the same time,the overproduction of ONOO^(-) exacerbates oxidative stress and inflammatory responses.This multiparameter assay is expected to improve the diagnostic accuracy of the early stages of RA,thus providing a scientific basis for early intervention and personalized treatment.
基金supported by the National Natural Science Foundation of China(Nos.82272067,81974386,M-0696,and 82273486)Natural Science Foundation of Hunan Province(Nos.2022JJ80052,2024JJ6596)the Innovation Fund for Postgraduate Students of Central South University(No.2023ZZTS0841)。
文摘Colorectal cancer(CRC)is one of the most prevalent malignant tumors worldwide,exhibiting high morbidity and mortality.Lack of efficient tools for early diagnosis and surgical resection guidance of CRC have been a serious threat to the long-term survival rate of the CRC patients.Recent studies have shown that relative higher viscosity was presented in tumor cells compared to that in normal cells,leading to viscosity as a potential biomarker for CRC.Herein,we reported the development of a series of novel viscosity-sensitive and mitochondria-specific fluorescent probes(HTB,HTI,and HTP)for CRC detection.Among them,HTB showed high sensitivity,minimal background interference,low cytotoxicity,and significant viscous response capability,making it an ideal tool for distinguishing colorectal tumor cells from normal cells.Importantly,we have successfully utilized HTB to visualize in a CRC-cells-derived xenograft(CDX)model,enriching its medical imaging capacity,which laid a foundation for further clinical translational application.
文摘The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optical microscope,scanning electron microscope,tensile test at room temperature,corrosion immersion tests and electrochemical measurements.The results show that the introduction of TIG arc during FSW process results in a more uniform microstructure of the joint with no tunnel hole defects.Furthermore,it enhances tensile strength and elongation of the joint with increased rates of 11.5%and 50.0%,respectively;meanwhile,the corrosion current density and largest corrosion depth are decreased with reduction rates of 78.2%and 45.7%,respectively.TIG-FSW can promote flow,contact and diffusion of materials,thus improving microstructure of the joint.Additionally,it reduces the size and number of secondary phase particles.Consequently,these factors contribute to the higher tensile properties and corrosion resistance of the joints.
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.
文摘This article provides a short review on the importance of the detailed analysis of a Langmuir probe I-V trace in a multi-Maxwellian plasma,and discuss proper procedures analyzing Langmuir probe I-V traces in bi-Maxwellian and triple-Maxwellian Electron Energy Distribution Function(EEDF)plasmas.Discus⁃sion and demonstration of procedures include the treatment of the ion saturation current,electron saturation cur⁃rent,space-charge effects on the I-V trace,and most importantly how to properly isolate and fit for each electron group present in an I-V trace reflecting a mult-Maxwellian EEDF,as well as how having a multi-Maxwellian EEDF affects the procedures of treating the ion and electron saturation currents.Shortcomings of common improp⁃er procedures are discussed and demonstrated with simulated I-V traces to show how these procedures gives false measurements.
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A new coumarin derivative C2 was constructed to act as a highly effective turn-on fluorescent probe for Cu^(2+)ions.The introduction of Cu^(2+)could lead to the hydrolytic cleavage of the phenylhydrazone moiety in C2 and the transformation into strongly fluorescent aldehyde C1.Probe C2 could recognize Cu^(2+)through a marked fluorescence enhancement with the detection limit as low as 150 nmol/L.By virtue of this unique catalytic hydrolysis reaction,compound C2 displayed highly selective response toward Cu^(2+)over other common ions even in the presence of excessive competitive ions.Furthermore,there was a good linear relationship between the intensity change and the concentration of Cu^(2+)ions,which was beneficial for the exactly quantitative detection.Especially,the efficient detection of Cu^(2+)with C2 for the practical application was successfully performed in gas-generating agents detection.
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.
