Purpose: Interferon-γ (INF-γ) is a cytokine that participates in the immune reaction of the body. Its level of secretion can reflect the immune response condition after the body is infected by pathogens, which is a ...Purpose: Interferon-γ (INF-γ) is a cytokine that participates in the immune reaction of the body. Its level of secretion can reflect the immune response condition after the body is infected by pathogens, which is a significant indication of clinically-related diseases. Therefore, it is of great significance in application to develop a fluorescence biosensor to inspect INF-γ with rapidness, high sensitivity and high practicability. Method: The fluorescence sensor is made on the basis of the two-dimensional nano-material namely Carbon Nitride Nanosheet (CNNS) and the Aptamer probe to identify INF-γ (Apt®INF-γ). CNNS can quickly quench the Cy5 fluorescent dye modified on the Apt®INF-γ probe due to the Photoinduced Electron Transfer (PET), but when the INF-γ exists, Apt®INF-γ specifically identifies and combines it. The complex of Apt®INF-γ and INF-γ is away from CNNS, which can effectively block the fluorescent signal of Apt?INF-γ being quenched by CNNS. Result: The sensitive detection of IFN-γ protein can be achieved through the application of CNNS/Apt®INF-γ fluorescence sensing platform. In this method, the intensity of the fluorescent signal is positively correlated with the concentration of IFN-γ, of which the liner response range is 0.5 - 100 ng/mL and the limit of detection is 0.303 ng/mL. In addition, this fluorescence sensing platform has the advantages of high specificity, simple operation and low costs. It can inspect the content of IFN-γ in clinical serum samples without interference. The actual recovery rate of serum samples is 97.11% - 106.96%. Conclusion: Therefore, the CNNS/Apt®INF-γ sensing platform is expected to be implemented in the actual clinical detection, also conducive to developing a universal fluorescence biosensor to inspect other target materials.展开更多
Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the ...Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the basis of MoS<sub>2</sub>NS fluorescence quenching property have become a research hotspot. Therefore, we can construct a fast and simple analysis method with high specificity to detect AFB<sub>1</sub> by utilizing MoS<sub>2</sub>NS, which can be effectively applied to food safety monitoring and clinical diagnosis. Method: In the current research, a fluorescence biosensor is developed on the basis of a new type of two-dimensional nano-material namely MoS<sub>2</sub>NS applied for the detection of AFB<sub>1</sub>. The fluorescence of Apt@AFB<sub>1</sub> can be quickly quenched by MoS<sub>2</sub>NS through the fluorescence resonance energy transfer (FRET). When the target molecule AFB<sub>1</sub> exists, after the specificity binding between AFB<sub>1</sub> and aptamer, the Apt@AFB<sub>1</sub> loses its single stranded structure and is away from MoS<sub>2</sub>NS, and the fluorescence of Apt®AFB<sub>1</sub> cannot be quenched effectively. Such sensing signals can be used to achieve the sensitive detection of AFB<sub>1</sub>. Result: With this new method, under the optimized conditions, the AFB<sub>1</sub> is analyzed in the MoS<sub>2</sub>NS/Apt®AFB<sub>1</sub> sensing platform. Within the dynamic range of 0.2 - 25 ng/mL, the sensing platform expresses a good linear response to the level of AFB<sub>1</sub> with the R<sup>2</sup> = 0.9964 and LOD as 90 pg/mL. This method is applied to detect the actual serum samples and soybean milk with the recovery rate of 93.10% - 107.23% and 95.15% - 102.60% separately, and it can be used in the quantitative detection under the interference of other mycotoxins in a relatively accurate way. Conclusion: It is proved that this new detection method can be used as a potential biosensor platform for the detection of AFB<sub>1</sub>. This detection method features several advantages such as specificity, rapidness and low costs, which can meet the requirement of trace detection in clinical detection and food safety.展开更多
The active oxygen species in the catalytic oxidation system of Fe(Ⅲ)PcTs-t-BuOOH were identified,and the mechanism of the catalytic oxidation of phenolic substrates was proposed.Quinone imine molecules,the main produ...The active oxygen species in the catalytic oxidation system of Fe(Ⅲ)PcTs-t-BuOOH were identified,and the mechanism of the catalytic oxidation of phenolic substrates was proposed.Quinone imine molecules,the main products of catalytic oxidation reaction,can be adsorbed on the surface of CdTe QDs,resulting in their fluorescence quenching.A dual function of catalytic oxidation and fluorescence sensing was developed for the determination of dichlorophenol(DCP)based on the Fe(Ⅲ)PcTs-BuOOH-CdTe QDs system.The linear detection range of DCP was 1×10^(-6)-1.3×10^(-4) mol/L,and the detection limit 2.4×10^(-7) mol/L.This method was characterized by high selectivity,good repeatability and desirable stability,presenting promising potentials for analyzing DCP concentration in real water samples.展开更多
The development of host-guest MOF luminescent composites has attracted considerable attention. However,it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal-organic framework (...The development of host-guest MOF luminescent composites has attracted considerable attention. However,it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal-organic framework (MOF) and modulate donor-acceptor interaction. Herein,a series of isostructural 3D porous lanthanide MOF [Ln_(2)(BINDI)0.5(NO_(3))(DMA)(H_(2)O)]∙DMA∙2.5H_(2)O (Ln = La (1),Ce (2),Pr (3) and Nd (4);H_(4)BINDI (N,N’-bis(5-isophthalic acid)-1,4,5,8-naphthalenediimide) were synthesized. Considering the electron-deficient performances of Ln-BINDI MOFs,D-A type composites Ln-MOFs (1—4@H_(4)TBAPy) were prepared via the incorporation of electron-rich H_(4)TBAPy (1,3,6,8-tetrakis(p-benzoic acid) pyrene),which more improved the luminescence performance of complexes 1—4 and can be used as fluorescence sensors for the detection of nitro compounds and aldehydes. High sensitivity of 1@H_(4)TBAPy towards pNBA,pNA PNP,DNP,and TNP could be achieved through hydrogen bond interactions between MOF and analytes,as well as the π-π interaction between H_(4)TBAPy and the naphthalene ring of BINDI,thus the fluorescence quenching efficiency of 1@H_(4)TBAPy was better than that of the complex 1. In addition,it is found that 1@H_(4)TBAPy has high selectivity and sensitivity to aromatic aldehyde SA,5-Mesal and HMBA. Such strategy to enhance the emission of NDI based Ln-BINDI MOFs,will open up an avenue to obtain more fluorescent MOFs for sensing.展开更多
By employing a rational approach,we prepared a novel kind of luminescent europium-centered hybrid material named Eu(tta)_(3)NCP-TiO_(2).The resulting material was characterized by FT-IR spectra,SEM,X-ray diffraction,t...By employing a rational approach,we prepared a novel kind of luminescent europium-centered hybrid material named Eu(tta)_(3)NCP-TiO_(2).The resulting material was characterized by FT-IR spectra,SEM,X-ray diffraction,thermogravimetric analysis,and photoluminescence spectra.The hybrid material features the combined advantages of the europium complex and the titania host,exhibiting not only good thermostability,but also long luminescence lifetime.Owing to the excellent luminescence of this material,the application in detecting organic small molecule solvents and metal ions was explored systematically.Significantly,Eu(tta)_(3)NCP-TiO_(2) exhibits superior detection for nitrobenzene molecule and Cu^(2+) ion in DMF(N,N-dimethylformamide) medium.Furthermore,the limit of detection(LOD) of Eu(tta)_(3)NCP-TiO_(2) for nitrobenzene and Cu^(2+) ion can be counted as 5.593× 10^(-5) and 9.566 ×10^(-5) mol/L,respectively.The results demonstrate that Eu(tta)_(3)NCP-TiO_(2) can serve as an efficient fluorescence probe for the detection of sensing of nitrobenzene and Cu^(2+) ion.展开更多
Based on the solvothermal reaction of 5,5΄-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthrolin-2-7-diyl)bis-1,3-benzenedicarboxylic acid(H4L)linker and Zn(Ⅱ)/ⅡCd(Ⅱ),two new 2D coordination polymers(CPs),namely{[ZnH2L(4,4...Based on the solvothermal reaction of 5,5΄-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthrolin-2-7-diyl)bis-1,3-benzenedicarboxylic acid(H4L)linker and Zn(Ⅱ)/ⅡCd(Ⅱ),two new 2D coordination polymers(CPs),namely{[ZnH2L(4,4΄-bibp)]·H2O}n(1)and{[CdL0.5(1,4-bimb)0.5(H2O)]·EtOH}n(2)(L=BIPA-TC),have been successfully constructed and characterized by EA,PXRD and IR with the aid of 4,4΄-bis(benzoimidazo-1-yl)biphenyl(4,4΄-bbib)/1,4-bis(imidazol-1-ylmethyl)benzene(1,4-bimb).The structural analysis showed that complex 1 exhibits a 3D supramolecular structure with the topology of sql,and complex 2 possesses a 2-nodal(4,6)-c framework with the topology of(32·42·52)(34·44·54·63)-4,6T26.Fluorescent experiments showed that 1 and 2 have high selectivity and sensitivity for the sensing of nitroaromatic compounds and Fe3+in aqueous solutions.展开更多
A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophtha...A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection concentrations.The sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime analyses.The activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade TCT.Both 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,respectively.The photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap experiments.The Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.展开更多
A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsula...A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsulated in polystyrene by a microencapsulation strategy.The CsPbBr_(3)-KSF-PS film shows good temperature sensing response from 30℃to 70℃,with a relative temperature sensitivity(Sr)up to 10.31%℃^(−1) at 45℃.Meanwhile,the film maintains more than 95%intensity after 6 heating-cooling cycles and keeps its fluorescence characteristics after 3 months.The film can be used to monitor temperature change by naked eye under a UV lamp.In particular,the temperature discoloration point of the sensing film can be controlled by the ratio change of CsPbBr_(3):KSF to expand its applications.The study of the CsPbBr_(3)-KSF-PS sensing mechanism in this work is helpful to provide effective strategies for the design of reliable,high sensitivity and stable temperature sensing system using CsPbBr_(3)NCs.展开更多
Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-guest properties and extensive applications. However, up to now, all the rep...Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-guest properties and extensive applications. However, up to now, all the reported water-soluble pillar[5]arenes acted as the host molecules, whereas they failed to be postsynthetically modified, which seriously impeded the development of the pillar[5]arene-based supramolecular chemistry. In this work, a new water-soluble pillar[5]arene, pillar[4]arene[1]quinone, was designed and synthsized with eight quaternary ammonium groups as well as a quinone units. Such a new water-soluble pillar[4]arene[1]quinone was capable of forming 1:1 stable complex with sodium 1-octanesulfonate in aqueous solution. Since the 1,4-quinone unit of WP[4]Q[1] could react with ethylenediamine (EDA) to form a conjugated quinoxaline structure, so pillar[4]arene[1]quinone could apply to the facile fluorescence turn-on sensing of EDA in aqueous solution, organic solvent and air.展开更多
Drug abuse directly endangers human health and social security,hence its sensitive and rapid detection is vitally important.In recent years,organic film-based fluorescent sensing technology has attracted more and more...Drug abuse directly endangers human health and social security,hence its sensitive and rapid detection is vitally important.In recent years,organic film-based fluorescent sensing technology has attracted more and more attention in the detection of drugs and explosives due to its advantages of simple operation and rapid detection.For film-based fluorescent sensors,in addition to sensitive materials,the surface morphology of the film is also an important factor affecting the performance.In previous studies,the regulation of surface morphology mainly depends on concentration changes or complex templates.Here,a novel fluorescent polymer probe was designed and synthesized,and a simple and efficient ultraviolet(UV)-ozone substrate treatment method is used to adjust their surface morphology.The results show that film has an excellent fluorescence enhancement effect upon exposure to methylphenethylamine(MPEA,a simulant of methamphetamine)vapor.The sensing effect of the film is significantly improved after UV-ozone substrate treatment,and the limit of detection was decreased by 10.4 times from 2.59 to 0.25 ppm.Further experiments show that the sensing performance of other fluorescent probe can also be improved by the UV-ozone substrate treatment.This convenient and general method may become a very effective approach to improve the performance of film-based fluorescent sensors.展开更多
A fluorescent cyclodextrin/carbon nanotube assembly was easily constructed through the non-covalent attach- ment of adamantanylpyrene on carbon nanotube and the following association of cyclodextrin derivative bearing...A fluorescent cyclodextrin/carbon nanotube assembly was easily constructed through the non-covalent attach- ment of adamantanylpyrene on carbon nanotube and the following association of cyclodextrin derivative bearing fluorescent substituent, and its structure was fully characterized by UV/Vis/NIR spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and atomic force microscopy. Fluorescence spectroscopic and fluorescence microscopic studies showed that the resultant non-covalently functionalized fluo- rescent nanotube could be used as a highly selective fluorescent probe for Zn2+ in both water and living cells. Without carbon nanotube, the fluorescence probe was unable to enter the cell but only anchored on the cell mem- brane. This approach will overcome the disadvantage of many spectral sensors that are unable to enter living cells and greatly improve the application of naotube-related supramolecular architecture in nanoscience and technology.展开更多
Saccharide sensing is a very meaningful research topic as saccharides are involved in many biological activities.However,it is challenging to design molecular sensors for saccharides because this family of compounds i...Saccharide sensing is a very meaningful research topic as saccharides are involved in many biological activities.However,it is challenging to design molecular sensors for saccharides because this family of compounds is hydromimetic in aqueous solutions and shares a similar chemical structure.In this review,research progress in the development of porphyrin-based saccharide sensors is described with representative examples.We focus on using porphyrin as the signal reporter because porphyrins exhibit unique advantages in high chemical stability,long emission wavelength,and multiple structural modification strategies.Reported literature results have been classified into mainly two sections according to the general working principles of the porphyrin sensor molecules.In the first section,recognition unit,design strategy and sensing performance of traditional porphyrin-based selective saccharide sensors are discussed.While in the second section,development of porphyrin-based sensor arrays for pattern recognition of saccharides has been summarized.Looking through the design strategy and sensing performance of reported achievements,it is reasonable to anticipate a bright future for designing practical porphyrin-based saccharide sensors.展开更多
Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linke...Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(HPTA), benzene-1,3,5-tricarboxylic acid(HBTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Feand CrO. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.展开更多
Particle image velocimetry(PIV)is an experimental technique that uses microscale particles as tracers to measure the velocity of a fluid flow.In this paper,we seek to extend this technique to simultaneously measure fl...Particle image velocimetry(PIV)is an experimental technique that uses microscale particles as tracers to measure the velocity of a fluid flow.In this paper,we seek to extend this technique to simultaneously measure fluid temperature as well,by employing a novel class of thermosensitive polymer particles.Towards this aim,we designed a process to encapsulate highly fluorescent thermosensitive NBD-AE-co-poly(N-isopropylacrylamide)polymers into optically transparent poly(dimethylsiloxane)particles.These novel PIV particles enable direct measurement of water velocity while serving as temperature probes that increase their fluorescence intensity when the temperature rises above 32°C.To demonstrate the ability of the particles to simultaneously serve as flow tracers and temperature sensors in water,we examine the flow velocity and temperature in the wake of a heated cylinder in a cross flow.Our results indicate the possibility of extending PIV to afford the spatial and temporal resolution of fluid velocity and temperature gradients in water,with potential application to the study of convection problems from life sciences to engineering.展开更多
Three Cd(II) metal-organic complexes, namely [Cd(phen)2Cl2](1), [Cd(phen)Cl2](2) and [Cd(phen)(cam)]. H2O(3)(phen=1,10-phenanthroline, H2cam=camphoric acid), were hydrothermally synthesized using Cd2...Three Cd(II) metal-organic complexes, namely [Cd(phen)2Cl2](1), [Cd(phen)Cl2](2) and [Cd(phen)(cam)]. H2O(3)(phen=1,10-phenanthroline, H2cam=camphoric acid), were hydrothermally synthesized using Cd2+, phen and Hacam as raw materials under different conditions of pH values, reaction temperatures or reactant ratios. The prepared complexes were structurally characterized by means of single-crystal X-ray diffraction, and the results show that complex 1 is a 2D supramolecular complex, which consists of [Cd(phen)2Cl2] mononuclear subunits, while complex 2 shows a 1D chain structure, in which Cd(II) ions are connected by chloride(Cl ) bridges, with phen hanging on both sides of the chain. No cam anions have been observed in the structures of complexes 1 and 2. In complex 3, cam connects Cd(lI) ions to construct a 2D network, in which phen acts as terminal ligands. The adjacent 1D chains for complex 2 and the adjacent 2D layers for complex 3 are further linked by hydrogen bonding interac- tions or π-π intermolecular interactions to form 3D supramolecular networks, respectively. The effects of reaction conditions on the assembly and structures of the complexes have been discussed. The fluorescent and photocatalytic properties of complexes 1-3 and the fluorescent sensing behaviors of complexes 2 and 3 have also been investigated.展开更多
Detection of N-acyl homoserine lactones (AHLs) is useful for understanding quorum sensing (QS) behaviors, including biofilm formation, virulence and metabolism. For detecting AHLs and indicating the host cells in ...Detection of N-acyl homoserine lactones (AHLs) is useful for understanding quorum sensing (QS) behaviors, including biofilm formation, virulence and metabolism. For detecting AHLs and indicating the host cells in situ, we constructed the plasmid pUCGMA2T1-4 to make a dual fluorescent whole- cell biosensor based on the AhlI/R AHL system of Pseudomonas syringae pv. syringae B728a. The plasmid contains three components: constitutively expressed enptll::gfP for indicating host cells, Pahll::mcherry that produces red fluorescence in response to AHL, and the ahIR gene that encodes an AHL regulatory protein. Meanwhile, two copies of T1-4 (four tandem copies of a transcriptional terminator) were added into the plasmid to reduce background. The results showed that when the plasmid was placed into Escherichia coli, the dual fluorescence whole-cell biosensor was able to respond with red fluorescence within 6 hr to 5 × 10^-8-1 × 10^-5 mol/L of 3OC6-HSL. Bright green fluorescence indicated the host cells. Furthermore, when the plasmid was transferred to wild- type Pseudomonas PhTA125 (an AHL-producing bacterium), it also showed both green and red fluorescence. This result demonstrates that this plasmid can be used to construct whole-cell indicators that can indicate the AHL response and spatial behaviors of microbes in a mi tal niche展开更多
The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much cr...The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much crucial and several researches are going on in this topic.Metal-organic frameworks (MOFs) are considered as an effective device for sensing of toxic heavy metal ions in water.The tunable functionalities with large surface area of highly semiconducting MOFs enhance its activity towards fluorescence sensing.In this study,we are reporting one highly selective and sensitive luminescent sensor for the detection of mercury (Ⅱ) in water.A series of binary MOF composites were synthesized using in-situ solvothermal synthetic technique for fluorescence sensing of Hg^(2+)in water.The welldistributed graphitic carbon nitride quantum dots on porous zirconium-based MOF improve Hg^(2+)sensing activity in water owing to their great electronic and optical properties.The binary MOF composite (2) i.e.,the sensor exhibited excellent limit of detection (LOD) value of 2.4 nmol/L for Hg^(2+).The sensor also exhibited excellent performance for mercury (Ⅱ)detection in real water samples.The characterizations of the synthesized materials were done using various spectroscopic techniques and the fluorescence sensing mechanism was studied.展开更多
With the rapid development of economy, industrial and agricultural pollutants have caused great damage to the ecological environment and the normal development of organisms, posing a serious threat to global public he...With the rapid development of economy, industrial and agricultural pollutants have caused great damage to the ecological environment and the normal development of organisms, posing a serious threat to global public health. Therefore, rapid and sensitive detection of pollutants is very important for environmental safety and people’s health. A stable multi-response fluorescence sensor(RhB@1) with dual emission characteristics was constructed by embedding Rh B guest molecules in Zn-MOF using a simple one-pot method. XRD, IR, XPS, Raman and other characterization methods were used to demonstrate the formation of composite materials. The sensor has two fluorescence emission peaks at 415 nm and 575nm under the excitation of 316 nm. It has high sensitivity and low detection limit(7.94 and 7.82 nmol/L,respectively) in the detection of fluazinam(FLU) and Fe^(3+). The mechanism of fluorescence quenching may be due to the synergistic effect of IFE and PET. Outstandingly, when ascorbate acid(AA) was added to the quenching system of Fe^(3+) and Rh B@1, its fluorescence gradually recovered, forming the unique“on-off-on” sensor. Therefore, RhB@1 has a fast fluorescence response and good stability, making it potentially useful in practical application and biosensors. More significantly, using Fe^(3+)and AA as chemical input signals, a binary intelligent logic gate device has been developed based on the “on-off-on” response mode of RhB@1, which extends the application of logic gate switching devices in the chemical field. In addition, a visual portable test paper with good selectivity and high sensitivity was developed, which can be used for rapid detection of FLU, showing its broad application prospect.展开更多
Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(...Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(CH_(3))_(2)NH_(2)][Zn_(3)(bbip)(BTDI)1.5(OH)]·DMF·MeOH·3H_(2)O}n(JXUST-13, bbip = 2,6-bis(benzimidazol-1-yl)pyridine and H_(4)BTDI = 5,5-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid)with new 4,4,8-connceted topology has been successfully synthesized and structurally characterized. Importantly, JXUST-13 could recognize H_(2)PO_(4)-and acetylacetone(Acac) by obvious fluorescence blue shift and slight enhancement with the detection limits of 2.70 μmol/L and 0.21 mmol/L, respectively. In addition, JXUST-13 exhibits relatively good thermal stability, chemical stabilities as well as reusability, and the analytes could be distinguished by naked eye and fluorescence test paper. Remarkably, JXUST-13 is the first dual-responsive MOF sensor based on fluorescence blue shift for the detection of H_(2)PO_(4)-and Acac with good selectivity in a handy, economic, and environmentally friendly manner.展开更多
文摘Purpose: Interferon-γ (INF-γ) is a cytokine that participates in the immune reaction of the body. Its level of secretion can reflect the immune response condition after the body is infected by pathogens, which is a significant indication of clinically-related diseases. Therefore, it is of great significance in application to develop a fluorescence biosensor to inspect INF-γ with rapidness, high sensitivity and high practicability. Method: The fluorescence sensor is made on the basis of the two-dimensional nano-material namely Carbon Nitride Nanosheet (CNNS) and the Aptamer probe to identify INF-γ (Apt®INF-γ). CNNS can quickly quench the Cy5 fluorescent dye modified on the Apt®INF-γ probe due to the Photoinduced Electron Transfer (PET), but when the INF-γ exists, Apt®INF-γ specifically identifies and combines it. The complex of Apt®INF-γ and INF-γ is away from CNNS, which can effectively block the fluorescent signal of Apt?INF-γ being quenched by CNNS. Result: The sensitive detection of IFN-γ protein can be achieved through the application of CNNS/Apt®INF-γ fluorescence sensing platform. In this method, the intensity of the fluorescent signal is positively correlated with the concentration of IFN-γ, of which the liner response range is 0.5 - 100 ng/mL and the limit of detection is 0.303 ng/mL. In addition, this fluorescence sensing platform has the advantages of high specificity, simple operation and low costs. It can inspect the content of IFN-γ in clinical serum samples without interference. The actual recovery rate of serum samples is 97.11% - 106.96%. Conclusion: Therefore, the CNNS/Apt®INF-γ sensing platform is expected to be implemented in the actual clinical detection, also conducive to developing a universal fluorescence biosensor to inspect other target materials.
文摘Purpose: Aflatoxin B<sub>1</sub> is the most common mycotoxin in cereal crops;it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the basis of MoS<sub>2</sub>NS fluorescence quenching property have become a research hotspot. Therefore, we can construct a fast and simple analysis method with high specificity to detect AFB<sub>1</sub> by utilizing MoS<sub>2</sub>NS, which can be effectively applied to food safety monitoring and clinical diagnosis. Method: In the current research, a fluorescence biosensor is developed on the basis of a new type of two-dimensional nano-material namely MoS<sub>2</sub>NS applied for the detection of AFB<sub>1</sub>. The fluorescence of Apt@AFB<sub>1</sub> can be quickly quenched by MoS<sub>2</sub>NS through the fluorescence resonance energy transfer (FRET). When the target molecule AFB<sub>1</sub> exists, after the specificity binding between AFB<sub>1</sub> and aptamer, the Apt@AFB<sub>1</sub> loses its single stranded structure and is away from MoS<sub>2</sub>NS, and the fluorescence of Apt®AFB<sub>1</sub> cannot be quenched effectively. Such sensing signals can be used to achieve the sensitive detection of AFB<sub>1</sub>. Result: With this new method, under the optimized conditions, the AFB<sub>1</sub> is analyzed in the MoS<sub>2</sub>NS/Apt®AFB<sub>1</sub> sensing platform. Within the dynamic range of 0.2 - 25 ng/mL, the sensing platform expresses a good linear response to the level of AFB<sub>1</sub> with the R<sup>2</sup> = 0.9964 and LOD as 90 pg/mL. This method is applied to detect the actual serum samples and soybean milk with the recovery rate of 93.10% - 107.23% and 95.15% - 102.60% separately, and it can be used in the quantitative detection under the interference of other mycotoxins in a relatively accurate way. Conclusion: It is proved that this new detection method can be used as a potential biosensor platform for the detection of AFB<sub>1</sub>. This detection method features several advantages such as specificity, rapidness and low costs, which can meet the requirement of trace detection in clinical detection and food safety.
基金Funded by the National Natural Science Foundation of China(No.61205062)the Hubei Provincial Department of Education Scientific Research Program Guidance Project(No.B2020282)。
文摘The active oxygen species in the catalytic oxidation system of Fe(Ⅲ)PcTs-t-BuOOH were identified,and the mechanism of the catalytic oxidation of phenolic substrates was proposed.Quinone imine molecules,the main products of catalytic oxidation reaction,can be adsorbed on the surface of CdTe QDs,resulting in their fluorescence quenching.A dual function of catalytic oxidation and fluorescence sensing was developed for the determination of dichlorophenol(DCP)based on the Fe(Ⅲ)PcTs-BuOOH-CdTe QDs system.The linear detection range of DCP was 1×10^(-6)-1.3×10^(-4) mol/L,and the detection limit 2.4×10^(-7) mol/L.This method was characterized by high selectivity,good repeatability and desirable stability,presenting promising potentials for analyzing DCP concentration in real water samples.
基金supported by Postgraduate Education Reform Project of Liaoning Province(No.394)the Fund of Liaoning Provincial Department of Education(LJKMZ 20221403)the grants of the National Natural Science Foundation of China(No.21571091).
文摘The development of host-guest MOF luminescent composites has attracted considerable attention. However,it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal-organic framework (MOF) and modulate donor-acceptor interaction. Herein,a series of isostructural 3D porous lanthanide MOF [Ln_(2)(BINDI)0.5(NO_(3))(DMA)(H_(2)O)]∙DMA∙2.5H_(2)O (Ln = La (1),Ce (2),Pr (3) and Nd (4);H_(4)BINDI (N,N’-bis(5-isophthalic acid)-1,4,5,8-naphthalenediimide) were synthesized. Considering the electron-deficient performances of Ln-BINDI MOFs,D-A type composites Ln-MOFs (1—4@H_(4)TBAPy) were prepared via the incorporation of electron-rich H_(4)TBAPy (1,3,6,8-tetrakis(p-benzoic acid) pyrene),which more improved the luminescence performance of complexes 1—4 and can be used as fluorescence sensors for the detection of nitro compounds and aldehydes. High sensitivity of 1@H_(4)TBAPy towards pNBA,pNA PNP,DNP,and TNP could be achieved through hydrogen bond interactions between MOF and analytes,as well as the π-π interaction between H_(4)TBAPy and the naphthalene ring of BINDI,thus the fluorescence quenching efficiency of 1@H_(4)TBAPy was better than that of the complex 1. In addition,it is found that 1@H_(4)TBAPy has high selectivity and sensitivity to aromatic aldehyde SA,5-Mesal and HMBA. Such strategy to enhance the emission of NDI based Ln-BINDI MOFs,will open up an avenue to obtain more fluorescent MOFs for sensing.
基金Project supported by the National Natural Science Foundation of China(21473133,21173164)。
文摘By employing a rational approach,we prepared a novel kind of luminescent europium-centered hybrid material named Eu(tta)_(3)NCP-TiO_(2).The resulting material was characterized by FT-IR spectra,SEM,X-ray diffraction,thermogravimetric analysis,and photoluminescence spectra.The hybrid material features the combined advantages of the europium complex and the titania host,exhibiting not only good thermostability,but also long luminescence lifetime.Owing to the excellent luminescence of this material,the application in detecting organic small molecule solvents and metal ions was explored systematically.Significantly,Eu(tta)_(3)NCP-TiO_(2) exhibits superior detection for nitrobenzene molecule and Cu^(2+) ion in DMF(N,N-dimethylformamide) medium.Furthermore,the limit of detection(LOD) of Eu(tta)_(3)NCP-TiO_(2) for nitrobenzene and Cu^(2+) ion can be counted as 5.593× 10^(-5) and 9.566 ×10^(-5) mol/L,respectively.The results demonstrate that Eu(tta)_(3)NCP-TiO_(2) can serve as an efficient fluorescence probe for the detection of sensing of nitrobenzene and Cu^(2+) ion.
基金Supported by the NSFC(No.21676258)the International Scientific and Technological Cooperation Projects of Shanxi Province(No.201803D421080)。
文摘Based on the solvothermal reaction of 5,5΄-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthrolin-2-7-diyl)bis-1,3-benzenedicarboxylic acid(H4L)linker and Zn(Ⅱ)/ⅡCd(Ⅱ),two new 2D coordination polymers(CPs),namely{[ZnH2L(4,4΄-bibp)]·H2O}n(1)and{[CdL0.5(1,4-bimb)0.5(H2O)]·EtOH}n(2)(L=BIPA-TC),have been successfully constructed and characterized by EA,PXRD and IR with the aid of 4,4΄-bis(benzoimidazo-1-yl)biphenyl(4,4΄-bbib)/1,4-bis(imidazol-1-ylmethyl)benzene(1,4-bimb).The structural analysis showed that complex 1 exhibits a 3D supramolecular structure with the topology of sql,and complex 2 possesses a 2-nodal(4,6)-c framework with the topology of(32·42·52)(34·44·54·63)-4,6T26.Fluorescent experiments showed that 1 and 2 have high selectivity and sensitivity for the sensing of nitroaromatic compounds and Fe3+in aqueous solutions.
基金Project supported by the National Natural Science Foundation of China(22063010)the Youth Innovation Team of Shaanxi Universities。
文摘A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection concentrations.The sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime analyses.The activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade TCT.Both 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,respectively.The photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap experiments.The Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.
基金financial supports by the Shenzhen Science and Technology Project(No.JCYJ20180306172823786)the National Natural Science Foundation of China(Nos.21876141,NFFTBS-J1310024)。
文摘A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsulated in polystyrene by a microencapsulation strategy.The CsPbBr_(3)-KSF-PS film shows good temperature sensing response from 30℃to 70℃,with a relative temperature sensitivity(Sr)up to 10.31%℃^(−1) at 45℃.Meanwhile,the film maintains more than 95%intensity after 6 heating-cooling cycles and keeps its fluorescence characteristics after 3 months.The film can be used to monitor temperature change by naked eye under a UV lamp.In particular,the temperature discoloration point of the sensing film can be controlled by the ratio change of CsPbBr_(3):KSF to expand its applications.The study of the CsPbBr_(3)-KSF-PS sensing mechanism in this work is helpful to provide effective strategies for the design of reliable,high sensitivity and stable temperature sensing system using CsPbBr_(3)NCs.
基金financially supported by the National Natural Science Foundation of China (No. 21801139)the Natural Science Foundation of Jiangsu Province (Nos. BK20180942, BK20190917)+1 种基金the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (No. 19KJB150015)the Six Talent Peak Projects in Jiangsu Province (No. XCL-085)。
文摘Water-soluble pillar[5]arenes are a class of typical macrocycles and have aroused tremendous attention for its easy to modify, abundant host-guest properties and extensive applications. However, up to now, all the reported water-soluble pillar[5]arenes acted as the host molecules, whereas they failed to be postsynthetically modified, which seriously impeded the development of the pillar[5]arene-based supramolecular chemistry. In this work, a new water-soluble pillar[5]arene, pillar[4]arene[1]quinone, was designed and synthsized with eight quaternary ammonium groups as well as a quinone units. Such a new water-soluble pillar[4]arene[1]quinone was capable of forming 1:1 stable complex with sodium 1-octanesulfonate in aqueous solution. Since the 1,4-quinone unit of WP[4]Q[1] could react with ethylenediamine (EDA) to form a conjugated quinoxaline structure, so pillar[4]arene[1]quinone could apply to the facile fluorescence turn-on sensing of EDA in aqueous solution, organic solvent and air.
基金supported by the National Natural Science Foundation of China(Nos.62022085,61901456,61831021,61731016,and 61771460)the National Key R&D Program of China(No.2018AAA0103100)the Science and Technology Commission of Shanghai Municipality(Nos.19YF1455700 and 19142203500).
文摘Drug abuse directly endangers human health and social security,hence its sensitive and rapid detection is vitally important.In recent years,organic film-based fluorescent sensing technology has attracted more and more attention in the detection of drugs and explosives due to its advantages of simple operation and rapid detection.For film-based fluorescent sensors,in addition to sensitive materials,the surface morphology of the film is also an important factor affecting the performance.In previous studies,the regulation of surface morphology mainly depends on concentration changes or complex templates.Here,a novel fluorescent polymer probe was designed and synthesized,and a simple and efficient ultraviolet(UV)-ozone substrate treatment method is used to adjust their surface morphology.The results show that film has an excellent fluorescence enhancement effect upon exposure to methylphenethylamine(MPEA,a simulant of methamphetamine)vapor.The sensing effect of the film is significantly improved after UV-ozone substrate treatment,and the limit of detection was decreased by 10.4 times from 2.59 to 0.25 ppm.Further experiments show that the sensing performance of other fluorescent probe can also be improved by the UV-ozone substrate treatment.This convenient and general method may become a very effective approach to improve the performance of film-based fluorescent sensors.
文摘A fluorescent cyclodextrin/carbon nanotube assembly was easily constructed through the non-covalent attach- ment of adamantanylpyrene on carbon nanotube and the following association of cyclodextrin derivative bearing fluorescent substituent, and its structure was fully characterized by UV/Vis/NIR spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and atomic force microscopy. Fluorescence spectroscopic and fluorescence microscopic studies showed that the resultant non-covalently functionalized fluo- rescent nanotube could be used as a highly selective fluorescent probe for Zn2+ in both water and living cells. Without carbon nanotube, the fluorescence probe was unable to enter the cell but only anchored on the cell mem- brane. This approach will overcome the disadvantage of many spectral sensors that are unable to enter living cells and greatly improve the application of naotube-related supramolecular architecture in nanoscience and technology.
基金financially supported by the National Natural Science Foundation of China(Nos.22278229,22131005 and 21904066)333 High Level Talent Project of Jiangsu Province.
文摘Saccharide sensing is a very meaningful research topic as saccharides are involved in many biological activities.However,it is challenging to design molecular sensors for saccharides because this family of compounds is hydromimetic in aqueous solutions and shares a similar chemical structure.In this review,research progress in the development of porphyrin-based saccharide sensors is described with representative examples.We focus on using porphyrin as the signal reporter because porphyrins exhibit unique advantages in high chemical stability,long emission wavelength,and multiple structural modification strategies.Reported literature results have been classified into mainly two sections according to the general working principles of the porphyrin sensor molecules.In the first section,recognition unit,design strategy and sensing performance of traditional porphyrin-based selective saccharide sensors are discussed.While in the second section,development of porphyrin-based sensor arrays for pattern recognition of saccharides has been summarized.Looking through the design strategy and sensing performance of reported achievements,it is reasonable to anticipate a bright future for designing practical porphyrin-based saccharide sensors.
文摘Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(HPTA), benzene-1,3,5-tricarboxylic acid(HBTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Feand CrO. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.
基金This research was conducted with the support of the National Science Foundation through Grant No.CBET-1332204The authors also acknowledge support from the Office of Naval Research through Grant No.N00014-10-1-0988,which has allowed the acquisition of equipment used in this studyThis work was supported by the Division of Chemical,Bioengineering,Environmental,and Transport Systems[1332204].
文摘Particle image velocimetry(PIV)is an experimental technique that uses microscale particles as tracers to measure the velocity of a fluid flow.In this paper,we seek to extend this technique to simultaneously measure fluid temperature as well,by employing a novel class of thermosensitive polymer particles.Towards this aim,we designed a process to encapsulate highly fluorescent thermosensitive NBD-AE-co-poly(N-isopropylacrylamide)polymers into optically transparent poly(dimethylsiloxane)particles.These novel PIV particles enable direct measurement of water velocity while serving as temperature probes that increase their fluorescence intensity when the temperature rises above 32°C.To demonstrate the ability of the particles to simultaneously serve as flow tracers and temperature sensors in water,we examine the flow velocity and temperature in the wake of a heated cylinder in a cross flow.Our results indicate the possibility of extending PIV to afford the spatial and temporal resolution of fluid velocity and temperature gradients in water,with potential application to the study of convection problems from life sciences to engineering.
文摘Three Cd(II) metal-organic complexes, namely [Cd(phen)2Cl2](1), [Cd(phen)Cl2](2) and [Cd(phen)(cam)]. H2O(3)(phen=1,10-phenanthroline, H2cam=camphoric acid), were hydrothermally synthesized using Cd2+, phen and Hacam as raw materials under different conditions of pH values, reaction temperatures or reactant ratios. The prepared complexes were structurally characterized by means of single-crystal X-ray diffraction, and the results show that complex 1 is a 2D supramolecular complex, which consists of [Cd(phen)2Cl2] mononuclear subunits, while complex 2 shows a 1D chain structure, in which Cd(II) ions are connected by chloride(Cl ) bridges, with phen hanging on both sides of the chain. No cam anions have been observed in the structures of complexes 1 and 2. In complex 3, cam connects Cd(lI) ions to construct a 2D network, in which phen acts as terminal ligands. The adjacent 1D chains for complex 2 and the adjacent 2D layers for complex 3 are further linked by hydrogen bonding interac- tions or π-π intermolecular interactions to form 3D supramolecular networks, respectively. The effects of reaction conditions on the assembly and structures of the complexes have been discussed. The fluorescent and photocatalytic properties of complexes 1-3 and the fluorescent sensing behaviors of complexes 2 and 3 have also been investigated.
基金supported by the National Natural Science Foundation of China (No. 2117145)
文摘Detection of N-acyl homoserine lactones (AHLs) is useful for understanding quorum sensing (QS) behaviors, including biofilm formation, virulence and metabolism. For detecting AHLs and indicating the host cells in situ, we constructed the plasmid pUCGMA2T1-4 to make a dual fluorescent whole- cell biosensor based on the AhlI/R AHL system of Pseudomonas syringae pv. syringae B728a. The plasmid contains three components: constitutively expressed enptll::gfP for indicating host cells, Pahll::mcherry that produces red fluorescence in response to AHL, and the ahIR gene that encodes an AHL regulatory protein. Meanwhile, two copies of T1-4 (four tandem copies of a transcriptional terminator) were added into the plasmid to reduce background. The results showed that when the plasmid was placed into Escherichia coli, the dual fluorescence whole-cell biosensor was able to respond with red fluorescence within 6 hr to 5 × 10^-8-1 × 10^-5 mol/L of 3OC6-HSL. Bright green fluorescence indicated the host cells. Furthermore, when the plasmid was transferred to wild- type Pseudomonas PhTA125 (an AHL-producing bacterium), it also showed both green and red fluorescence. This result demonstrates that this plasmid can be used to construct whole-cell indicators that can indicate the AHL response and spatial behaviors of microbes in a mi tal niche
文摘The presence of toxic mercury (Ⅱ) in water is an ever-growing problem on earth that has various harmful effect on human health and aquatic living organisms.Therefore,detection of mercury (Ⅱ) in water is very much crucial and several researches are going on in this topic.Metal-organic frameworks (MOFs) are considered as an effective device for sensing of toxic heavy metal ions in water.The tunable functionalities with large surface area of highly semiconducting MOFs enhance its activity towards fluorescence sensing.In this study,we are reporting one highly selective and sensitive luminescent sensor for the detection of mercury (Ⅱ) in water.A series of binary MOF composites were synthesized using in-situ solvothermal synthetic technique for fluorescence sensing of Hg^(2+)in water.The welldistributed graphitic carbon nitride quantum dots on porous zirconium-based MOF improve Hg^(2+)sensing activity in water owing to their great electronic and optical properties.The binary MOF composite (2) i.e.,the sensor exhibited excellent limit of detection (LOD) value of 2.4 nmol/L for Hg^(2+).The sensor also exhibited excellent performance for mercury (Ⅱ)detection in real water samples.The characterizations of the synthesized materials were done using various spectroscopic techniques and the fluorescence sensing mechanism was studied.
基金supported by National Natural Science Foundation of China(No.21763028)Science and Technology project of Shaanxi Province(Nos.2022NY-071,2022QFY07-05,2022JZ-49)。
文摘With the rapid development of economy, industrial and agricultural pollutants have caused great damage to the ecological environment and the normal development of organisms, posing a serious threat to global public health. Therefore, rapid and sensitive detection of pollutants is very important for environmental safety and people’s health. A stable multi-response fluorescence sensor(RhB@1) with dual emission characteristics was constructed by embedding Rh B guest molecules in Zn-MOF using a simple one-pot method. XRD, IR, XPS, Raman and other characterization methods were used to demonstrate the formation of composite materials. The sensor has two fluorescence emission peaks at 415 nm and 575nm under the excitation of 316 nm. It has high sensitivity and low detection limit(7.94 and 7.82 nmol/L,respectively) in the detection of fluazinam(FLU) and Fe^(3+). The mechanism of fluorescence quenching may be due to the synergistic effect of IFE and PET. Outstandingly, when ascorbate acid(AA) was added to the quenching system of Fe^(3+) and Rh B@1, its fluorescence gradually recovered, forming the unique“on-off-on” sensor. Therefore, RhB@1 has a fast fluorescence response and good stability, making it potentially useful in practical application and biosensors. More significantly, using Fe^(3+)and AA as chemical input signals, a binary intelligent logic gate device has been developed based on the “on-off-on” response mode of RhB@1, which extends the application of logic gate switching devices in the chemical field. In addition, a visual portable test paper with good selectivity and high sensitivity was developed, which can be used for rapid detection of FLU, showing its broad application prospect.
基金supported by the National Natural Science Foundation of China (Nos. 22061019, 21861018, 22161019 and 12174172)the NSF of Jiangxi Province (No. 20202ACBL213001)+4 种基金Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry(No. 20212BCD42018)Fujian Key Laboratory of Functional Marine Sensing Materials,Minjiang University (No. MJUKF-FMSM202010)the Youth Jinggang Scholars Program in Jiangxi Province (No.QNJG2019053)the Two Thousand Program in Jiangxi Province (No.jxsq2019201068)the Special Foundation for Postgraduate Innovation in Jiangxi Province (No. YC_(2)020-B155)。
文摘Fluorescence detecting both organic and inorganic analytes has aroused tremendous scientific interests, because fluorescence techniques have high sensitivity and are easy to operate. A new threedimensional(3D) MOF {[(CH_(3))_(2)NH_(2)][Zn_(3)(bbip)(BTDI)1.5(OH)]·DMF·MeOH·3H_(2)O}n(JXUST-13, bbip = 2,6-bis(benzimidazol-1-yl)pyridine and H_(4)BTDI = 5,5-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid)with new 4,4,8-connceted topology has been successfully synthesized and structurally characterized. Importantly, JXUST-13 could recognize H_(2)PO_(4)-and acetylacetone(Acac) by obvious fluorescence blue shift and slight enhancement with the detection limits of 2.70 μmol/L and 0.21 mmol/L, respectively. In addition, JXUST-13 exhibits relatively good thermal stability, chemical stabilities as well as reusability, and the analytes could be distinguished by naked eye and fluorescence test paper. Remarkably, JXUST-13 is the first dual-responsive MOF sensor based on fluorescence blue shift for the detection of H_(2)PO_(4)-and Acac with good selectivity in a handy, economic, and environmentally friendly manner.