Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix ma...Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).展开更多
New HPLC method was developed for determination of amlodipine and valsartan in their binary mixture as a part of routine control of combined formulations. The method was validated to meet official requirements includi...New HPLC method was developed for determination of amlodipine and valsartan in their binary mixture as a part of routine control of combined formulations. The method was validated to meet official requirements including selectivity, stability, linearity, precision and accuracy. Chromatography was carried out using a LiChrospher RP-18 column, a mixture containing acetonitrile, phosphate buffer of pH 3.5 and methanol (45:45:10, v/v/v) and new fluorescence detection at 255 nm for excitation and 448 nm for emission. The effect of methanol content, pH of the buffer, flow rate, detection wavelengths and column temperature was estimated in robustness study, according to a plan defined by the Plackett-Burman design. For identification of significant effects, both graphical and statistical methods were used. Ro-bustness for dissolution test was checked estimating the effects of paddle speed, temperature and pH of dissolution medium. The method was proved to complying with all official guidelines. Therefore, it is suitable for determination of amlodipine and valsartan in their binary mixtures for different analytical and pharmaceutical purposes.展开更多
5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in al...5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in all mammalian tissues and high structural similarity with other cytosine derivatives, the precise and sensitive detection of 5fC is challenging. Herein, a photo-elutable and template-free isothermal amplification strategy has been proposed for the sensitive detection of 5fC in genomic DNA based on5fC-specific biotinylation, enrichment, photocleavage, and terminal deoxynucleotidyl transferase(Td T)-assisted fluorescence signal amplification, which is termed 5fC-PTIAS. By introducing the highly specific chemolabeling and the one-step photoelution processes, this strategy possesses a minimal nonspecific background as well as a much higher amplification efficiency. With the high signal-to-noise ratio, this strategy can achieve the accurate quantification of 5fC in various biological samples including mouse brain, kidney, and liver, with a limit of detection(LOD) of 0.025‰ in DNA(S/N=3). These results not only confirm the widespread distribution of 5fC but also indicate its significant variation in different tissues and ages. The bisulfite-and mass spectrometry-free strategy is highly sensitive, selective, and easily mastered, holding great promise in detecting other epigenetic modifications with much lower levels.展开更多
The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit...The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit competitive fluorescence detection performance of chloride ion(Cl)in aqueous solutio n.Under the optimized conditions,the concentration of Cl could be quantitative analyzed with the Ag-PCN in a wide detection range from 0.5 mmol/L to 0.1 mol/L,with a low detection limitation of 0.06 mmol/L.It is confirmed that the fluorescence of PCN could be effectively decayed by the photoinduced charge transfer via the adsorbed Cl for trapping holes,mainly by means of the time-resolved fluorescence and surface photo voltage spectra.The porous structure and modified Ag promote the adsorption of Cl on resulting Ag-PCN,leading to excellent fluorescence detection for Cl.This work provides a feasible route to develop a fluorescence detection of Cl with g-C_(3)N_(4) nanosheets in environment water.展开更多
A novel pseudo confocal microarray scanner is introduced, in which one dimension scanning is performed by a galvanometer optical scanner and a telecentric objective, another dimension scanning is performed by a steppi...A novel pseudo confocal microarray scanner is introduced, in which one dimension scanning is performed by a galvanometer optical scanner and a telecentric objective, another dimension scanning is performed by a stepping motor.展开更多
Conjugated microporous polymers(CMPs)are a kind of porous skeleton polymers,which are characterized by extended conjugated skeletons,large specific surface area and structure stability.In this work,a facile and versat...Conjugated microporous polymers(CMPs)are a kind of porous skeleton polymers,which are characterized by extended conjugated skeletons,large specific surface area and structure stability.In this work,a facile and versatile method was developed to fabricate flexible conjugated microporous polymer films for fast detecting the total quantity of developing agents and their oxidation products.Conjugated microporous polymer films were synthesized through in situ one-step approach by Suzuki coupling reaction.With such merits such as intense luminescence,easy synthesis and disposability,the polymer films were employed to detect developers based on fluorescence quenching in the printing wastewater.A linear response to p-benzoquinone,oxidation product of developers,was obtained in the range of 0.05-0.5 lmolL-1,with a detection limit of 0.015 lmolL-1.The strategy for in situ growth of flexible polyphenylene-conjugated microporous polymer(PP-CMP)films seems to be a very portable and general method for meeting different analytic purposes.展开更多
Biomass-derived carbon dots(C-dots)are considered a very important carbon material in metal ion detection of their small environmental impact,simple preparation process,and relatively low cost.A green approach for syn...Biomass-derived carbon dots(C-dots)are considered a very important carbon material in metal ion detection of their small environmental impact,simple preparation process,and relatively low cost.A green approach for synthesizing biomass-derived C-dots from Chenpi using a hydrothermal method without further processing is proposed in the present study.The as-synthesized C-dots show excellent fluorescence properties,superior resistance to UV irradiation photobleaching,and high photostability in salt-containing solutions.The C-dots were used in the form of label-free fluorescent probes for sensitively detecting Hg^(2+)selectively.The outcome relationship behaved linearly and was established based on a given range between 10–300 nM concentration,with a detection limit of 7.0 nM.This green strategy obtains a high C-dot quantum yield of 10.8%and satisfactory results in detecting Hg^(2+)in actual water samples.展开更多
Short-chain perfluorocarboxylic acids(PFCAs) are a class of persistent organic pollutants that are widely used as substitutes for long-chain PFCAs. However, they also pose a non-negligible risk to ecosystems. In this ...Short-chain perfluorocarboxylic acids(PFCAs) are a class of persistent organic pollutants that are widely used as substitutes for long-chain PFCAs. However, they also pose a non-negligible risk to ecosystems. In this study, we demonstrated that a fluorescent metal–organic framework(MOF)(named V-101) constructed from In^(3+)and an aromatic-rich tetratopic carboxylate ligand 5-[2,6-bis(4-carboxyphenyl) pyridin-4-yl] isophthalic acid(H4BCPIA) exhibited highly efficient turn-off and turn-on fluorescence responses toward five short-chain PFCAs in water and methanol, respectively. The limits of detection of V-101 toward five short-chain PFCAs are down to μg/L level, and it showed good anti-interference abilities toward short-chain PFCAs in the presence of common metal ions. The major mechanisms associated with fluorescence responses were molecular collisions and interactions between V-101 and short-chain PFCAs. This work demonstrates that the structure variety of MOFs imparts them with the potential of MOFs in the detection of short-chain PFCAs for pollution control.展开更多
The nitrogen-doped carbon dots(N-CDs)were prepared by using coke powder as carbon source and one-step hydrothermal method.The N-CDs were studied as a fluorescent chemosensor for determining Cr(Ⅵ)in water.The selectiv...The nitrogen-doped carbon dots(N-CDs)were prepared by using coke powder as carbon source and one-step hydrothermal method.The N-CDs were studied as a fluorescent chemosensor for determining Cr(Ⅵ)in water.The selective,sensitive,reproducibility and stability of as-prepared N-CDs were investigated.The morphology,composition and properties of N-CDs were characterized by a series of methods.The fluorescence quenching of N-CDs by Cr(Ⅵ)was explored.The experimental results reveal that the obtained N-CDs have great hydrophilicity and strong luminescence properties,which demonstrates the successful doping of nitrogen into the CDs.The surface-active groups and emission wavelength range of CDs increase due to the electronegativity and electron donor effect of doping N atom.Furthermore,the N-CDs exhibit good photochemical properties for the detection of Cr(Ⅵ),including a wide linear range from 0.3 to 200μM(R^(2)=0.9935)and a low detection limit of 0.10μM at the signal-to-noise ratio of 3(S/N=3).Moreover,the N-CDs as a sensor was used successfully for Cr(Ⅵ)detection in real water samples with recovery rates of 99.9%-110.6%.This sensor also shows highly reproducibility and stability.The N-CDs fluorescent chemical sensor may be a potential candidate for applying in the field of other fluorescent chemical sensing,catalysis,photoelectric devices and other fields.展开更多
In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluoresc...In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluorescent indicator,a flow-focusing channel for generating droplets in oil,and a long storage channel for incubating and detecting the droplets.By monitoring the fluorescence intensity of the droplets,the device could detect changes in solution accurately over time.The chip can generate droplets at frequencies of up to 42 Hz with a mixing ratio of 1:1 and a temporal resolution of 3–6 s.It had excellent linearity in detecting fluorescein solution in the concentration range 1–5μM.This droplet microfluidic chip provides several advantages over traditional methods,including high temporal resolution,stable droplet generation,and faster flow rates.This approach could be applied to monitoring calcium ions with a dynamic range from 102 to 107 nM and a detection limit of 10 nM.展开更多
Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing...Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing on organic FNPs has not been achieved to date.Herein,we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene-based bis-ureidopyrimidinone monomers(bis-UPys)to relate the size to the fluorescence of organic nanoparticles.At an equal concentration of bis-UPys,a logarithmic relationship between them is built with a correlation coefficient higher than 0.96.Theoretical calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the nanoparticles.This leads to different nonradiative decay rates of the embedded and exposed bis-UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface areas.The established fluorescence intensity-size correlation possesses fine universality and reliability,and it is successfully utilized to estimate the sizes of other nanoparticles,including those in highly diluted dispersions of FNPs.This work paves a new way for the simple and real-time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.展开更多
Ti_(2)C quantum dots(QDs)with rich surface functional groups have been synthesized using a hydrothermal method,and used to detect tetracycline(Tc)based on enhanced fluorescence.The interaction between the surface func...Ti_(2)C quantum dots(QDs)with rich surface functional groups have been synthesized using a hydrothermal method,and used to detect tetracycline(Tc)based on enhanced fluorescence.The interaction between the surface functional groups of Ti_(2)C QDs and Tc enhanced the fluorescence of Tc at 514 nm,which is used to detect Tc quickly and accurately.Under optimal conditions,the fluorescence intensity was linear to the concentration of Tc in the range of 50.0–30.0μM,with a detection limit of 21.6 nM.Furthermore,the Tc-Ti_(2)C QDs detection system was evaluated for detection of Tc in milk and artificial urine.This study demonstrates a new and simple strategy for Tc detection,which is important for food safety and human health.展开更多
Tadalafil(TAD)and dapoxetine HCl(DAP)are recently co-formulated and both show native fluorescence.Therefore,a novel,accurate,specific and sensitive reversed-phase high performance liquid chromatographic method with fl...Tadalafil(TAD)and dapoxetine HCl(DAP)are recently co-formulated and both show native fluorescence.Therefore,a novel,accurate,specific and sensitive reversed-phase high performance liquid chromatographic method with fluorescence detection was developed and validated for their separation and quantitation in dosage form and human plasma using avanafil as an internal standard(IS).Separation was achieved using isocratic elution within 7.0 min on C18column and acetonitrile-0.15%triethylamine(40∶60,v/v;pH 4)as a mobile phase.The flow rate was 1.0 mL/min and the detection was time-programmed at 330,410 and 370 nm for TAD,DAP and IS,respectively,after excitation at 236 nm.The linear ranges from 0.01 to 30.00μg/mL for each drug with the limits of detection of 4.20 and 7.20 ng/mL for TAD and DAP,respectively.The method was validated in accordance to the International Conference on Harmonization(ICH)guidelines and was successfully applied to spiked human plasma with mean recoveries of 98.17%and 98.83%for TAD and DAP respectively.展开更多
Microbial activity in the water injection system in oil and gas industry leads to an array of challenges, including biofouling, injectivity loss, reservoir plugging, and microbiologically influenced corrosion (MIC). A...Microbial activity in the water injection system in oil and gas industry leads to an array of challenges, including biofouling, injectivity loss, reservoir plugging, and microbiologically influenced corrosion (MIC). An effective mitigation strategy requires online and real-time monitoring of microbial activity and growth in the system so that the operators can apply and adjust counter-measures quickly and properly. The previous study [1] identified DNA staining technology-with PicoGreen and SYBR Green dyes—as a very promising method for automated, online determination of microbial cell abundance in the vast Saudi Aramco injection seawater systems. This study evaluated DNA staining technology on detection limit, automation potential, and temperature stability for the construction of automated sensor prototype. DNA staining with SYBR Green dye was determined to be better suited for online and real-time monitoring of microbial activity in the Saudi Aramco seawater systems. SYBR Green staining does not require sample pre-treatment, and the fluorescence signal intensity is more stable at elevated temperatures up to 30℃. The lower detection limit of 2 × 10<sup>3</sup>/ml was achieved under the optimized conditions, which is sufficient to detect microbial numbers in Saudi Aramco injection seawater. Finally, the requirements for design and construction of SYBR-based automated sensor prototype were determined.展开更多
Microbial activity is the cause of a variety of problems in water injection systems, e.g., microbial corrosion, plugging, and biofouling. Efficient monitoring of Saudi Aramco’s vast water injection system requires th...Microbial activity is the cause of a variety of problems in water injection systems, e.g., microbial corrosion, plugging, and biofouling. Efficient monitoring of Saudi Aramco’s vast water injection system requires the development of online and automated technologies for monitoring microbial activities in the system. A previous system review and technology screening has identified five single-analyte strategies [1], which were evaluated in this study with a laboratory-scale setup to determine their applicability for automated determination of microbial activity in the injection water system. Four of the five single-analyte measuring principles tested in the laboratory setup were deemed less suitable for automation and/or reliable for use in the detection of microbial activity in the company injection water system. These four principles were: luminescence assay for adenosine-5’-triphosphate (ATP), detection and electrochemical measurements of H<sub>2</sub>S, determination of pH by electrochemical sensor, and measurement of oxidation-reduction potential (ORP). The strategy of staining cells with fluorescent DNA dyes, followed by quantification of fluorescence signals, was identified to hold, with proper optimization of DNA staining and fluorescence detection, a very promising potential for integration in automated, online sensors for microbial activity in the injection water system.展开更多
Anovel metal-organic framework{[In_(3)(TATAT)_(2)]·3CH_(3)NH_(3)·7NMF·8H_(2)O}[JLU-MOF101,H_(6)TATAT=5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris-(azanediyl)triisophthalate,NMF=N-methyl-formamide]with cor...Anovel metal-organic framework{[In_(3)(TATAT)_(2)]·3CH_(3)NH_(3)·7NMF·8H_(2)O}[JLU-MOF101,H_(6)TATAT=5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris-(azanediyl)triisophthalate,NMF=N-methyl-formamide]with cor topology has been synthesized under solvothermal conditions.The framework of JLU-MOF101 is constructed by{In(COO)_(4)}-nodes and a hexacarboxylic organic ligand.JLU-MOF101 exhibits excellent fluorescence properties in N,N-dimethylformamide(DMF)solution,and its emission spectrum can be greatly overlapped with the ultraviolet absorption spectra of trinitrophenol(TNP)and 2,4-dinitrophenol(2,4-DNP).As a result,JLU-MOF101 exhibits excellent performance of fluorescence quenching for TNP and 2,4-DNP.In addition,we demonstrate the selective detection capability of JLU-MOF101 through a large number of anti-interference tests.展开更多
In this work,polymethacrylic acid(PMAA)-templated silver nanoclusters(Ag NCs)were developed as the fluorescent probe for the efficient and sensitive detection of adenosine triphosphate(ATP)in a wide range of pH values...In this work,polymethacrylic acid(PMAA)-templated silver nanoclusters(Ag NCs)were developed as the fluorescent probe for the efficient and sensitive detection of adenosine triphosphate(ATP)in a wide range of pH values.The fluorescence intensity of the Ag NCs could keep stable with pH values ranging from2.5 to 9.3.The detection of ATP was based on the quenching of the fluorescent Ag NCs in the presence of ATP.The fluorescence quenching of the Ag NCs with increasing ATP concentration was studied at pH 2.5,4.5,7.0 and 8.5 which involved a wide pH environment in body fluids.The limit of detection(LOD)for ATP was as low as 0.1 mmol/L in an acidic environment with pH of 2.5 and all the linear correlation coefficients were satisfactory under wide-span pH values from 2.5 to 8.5.In addition,the sensitive determination of ATP was also achieved by adding copper ions(Cu^2+).The high selectivity and rapid detection process proved that the fluorescent probe had great potential to detect ATP in biological samples under different pH conditions.展开更多
Formaldehyde(FA,a typical reactive carbonyl species)is a well-known environmental pollutant and a disease-related biomarker,making its sensitive and selective detection significant.Fluorescent probes have been explore...Formaldehyde(FA,a typical reactive carbonyl species)is a well-known environmental pollutant and a disease-related biomarker,making its sensitive and selective detection significant.Fluorescent probes have been explored for FA perception in environment,intracellular media and in vivo.In this review,we majorly conclude the recently represented fluorescence FA analysis based on small molecule probes.The general FA sensing mechanisms are first introduced.Regarding the FA detection in various environments,sensing tactics and performances are discussed in order of natural environment,living cells and in vivo.In the end,this review discusses the challenges and future trends of FA detection based on fluorescent probes.展开更多
基金supported by the Gansu Natural Science Foundation (Nos.20JR10RA778 and 20JR10RA777)。
文摘Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).
文摘New HPLC method was developed for determination of amlodipine and valsartan in their binary mixture as a part of routine control of combined formulations. The method was validated to meet official requirements including selectivity, stability, linearity, precision and accuracy. Chromatography was carried out using a LiChrospher RP-18 column, a mixture containing acetonitrile, phosphate buffer of pH 3.5 and methanol (45:45:10, v/v/v) and new fluorescence detection at 255 nm for excitation and 448 nm for emission. The effect of methanol content, pH of the buffer, flow rate, detection wavelengths and column temperature was estimated in robustness study, according to a plan defined by the Plackett-Burman design. For identification of significant effects, both graphical and statistical methods were used. Ro-bustness for dissolution test was checked estimating the effects of paddle speed, temperature and pH of dissolution medium. The method was proved to complying with all official guidelines. Therefore, it is suitable for determination of amlodipine and valsartan in their binary mixtures for different analytical and pharmaceutical purposes.
基金supported by the Scientific Technology Project of Shenzhen City(Nos.JCYJ20200109142410170 and JCYJ20210324124003008)the National Natural Science Foundation of China(No.21974153)+2 种基金the Scientific Technology Project of Guangzhou City(No.202103000003)the Guangdong Natural Science Foundation(No.2019A1515010587)the Guangdong Science and Technology Plan Project(No.2020B1212060077)。
文摘5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in all mammalian tissues and high structural similarity with other cytosine derivatives, the precise and sensitive detection of 5fC is challenging. Herein, a photo-elutable and template-free isothermal amplification strategy has been proposed for the sensitive detection of 5fC in genomic DNA based on5fC-specific biotinylation, enrichment, photocleavage, and terminal deoxynucleotidyl transferase(Td T)-assisted fluorescence signal amplification, which is termed 5fC-PTIAS. By introducing the highly specific chemolabeling and the one-step photoelution processes, this strategy possesses a minimal nonspecific background as well as a much higher amplification efficiency. With the high signal-to-noise ratio, this strategy can achieve the accurate quantification of 5fC in various biological samples including mouse brain, kidney, and liver, with a limit of detection(LOD) of 0.025‰ in DNA(S/N=3). These results not only confirm the widespread distribution of 5fC but also indicate its significant variation in different tissues and ages. The bisulfite-and mass spectrometry-free strategy is highly sensitive, selective, and easily mastered, holding great promise in detecting other epigenetic modifications with much lower levels.
基金the NSFC project(Nos.U1805255,11704105)Heilongjiang PostdoctoralFund(No.LBH-Z17188)the Fundamental Research Funds of University in Heilongjiang Province(No.2017-KYYWF-0465)。
文摘The porous g-C_(3)N_(4)(PCN)nanosheets are successfully synthesized and further modified with nano-sized Ag by a simple wet-chemical process.Intere stingly,the Ag-modified porous g-C_(3)N_(4)(Ag-PCN)nanosheets exhibit competitive fluorescence detection performance of chloride ion(Cl)in aqueous solutio n.Under the optimized conditions,the concentration of Cl could be quantitative analyzed with the Ag-PCN in a wide detection range from 0.5 mmol/L to 0.1 mol/L,with a low detection limitation of 0.06 mmol/L.It is confirmed that the fluorescence of PCN could be effectively decayed by the photoinduced charge transfer via the adsorbed Cl for trapping holes,mainly by means of the time-resolved fluorescence and surface photo voltage spectra.The porous structure and modified Ag promote the adsorption of Cl on resulting Ag-PCN,leading to excellent fluorescence detection for Cl.This work provides a feasible route to develop a fluorescence detection of Cl with g-C_(3)N_(4) nanosheets in environment water.
文摘A novel pseudo confocal microarray scanner is introduced, in which one dimension scanning is performed by a galvanometer optical scanner and a telecentric objective, another dimension scanning is performed by a stepping motor.
基金The work were supported by the National Natural Science Foundation of China(Nos.21575168,21277176,21475153 and 21675178)the Guangdong Provincial Natural Science Foundation of China(No.2015A030311020)+1 种基金the Special Funds for Public Welfare Research and Capacity Building in Guangdong Province of China(No.2015A030401036)the Guangzhou Science and Technology Program of China(No.201604020165),respectively。
文摘Conjugated microporous polymers(CMPs)are a kind of porous skeleton polymers,which are characterized by extended conjugated skeletons,large specific surface area and structure stability.In this work,a facile and versatile method was developed to fabricate flexible conjugated microporous polymer films for fast detecting the total quantity of developing agents and their oxidation products.Conjugated microporous polymer films were synthesized through in situ one-step approach by Suzuki coupling reaction.With such merits such as intense luminescence,easy synthesis and disposability,the polymer films were employed to detect developers based on fluorescence quenching in the printing wastewater.A linear response to p-benzoquinone,oxidation product of developers,was obtained in the range of 0.05-0.5 lmolL-1,with a detection limit of 0.015 lmolL-1.The strategy for in situ growth of flexible polyphenylene-conjugated microporous polymer(PP-CMP)films seems to be a very portable and general method for meeting different analytic purposes.
基金financially supported by the Development Program of Hunan Province (No.2020SK2128).
文摘Biomass-derived carbon dots(C-dots)are considered a very important carbon material in metal ion detection of their small environmental impact,simple preparation process,and relatively low cost.A green approach for synthesizing biomass-derived C-dots from Chenpi using a hydrothermal method without further processing is proposed in the present study.The as-synthesized C-dots show excellent fluorescence properties,superior resistance to UV irradiation photobleaching,and high photostability in salt-containing solutions.The C-dots were used in the form of label-free fluorescent probes for sensitively detecting Hg^(2+)selectively.The outcome relationship behaved linearly and was established based on a given range between 10–300 nM concentration,with a detection limit of 7.0 nM.This green strategy obtains a high C-dot quantum yield of 10.8%and satisfactory results in detecting Hg^(2+)in actual water samples.
基金the financial support from the National Natural Science Foundation of China (Nos.22225803 and 22038001)。
文摘Short-chain perfluorocarboxylic acids(PFCAs) are a class of persistent organic pollutants that are widely used as substitutes for long-chain PFCAs. However, they also pose a non-negligible risk to ecosystems. In this study, we demonstrated that a fluorescent metal–organic framework(MOF)(named V-101) constructed from In^(3+)and an aromatic-rich tetratopic carboxylate ligand 5-[2,6-bis(4-carboxyphenyl) pyridin-4-yl] isophthalic acid(H4BCPIA) exhibited highly efficient turn-off and turn-on fluorescence responses toward five short-chain PFCAs in water and methanol, respectively. The limits of detection of V-101 toward five short-chain PFCAs are down to μg/L level, and it showed good anti-interference abilities toward short-chain PFCAs in the presence of common metal ions. The major mechanisms associated with fluorescence responses were molecular collisions and interactions between V-101 and short-chain PFCAs. This work demonstrates that the structure variety of MOFs imparts them with the potential of MOFs in the detection of short-chain PFCAs for pollution control.
基金by the National Nature Science Foundation of China(61904130)the Open Fund of the Fujian Universities and Colleges Engineering Research Center of Modern Facility Agriculture of Fujian University(G2-KF2002)+4 种基金the Opening Project of Key Laboratory of Optoelectronic Chemical Materials and Devices,Ministry of Education,Jianghan University(JDGD202017)the Open Fund of the Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steel Making(Wuhan University of Science and Technology)of China(KF-20-5)the Fund of Hangzhou Meishi Technology Co.,Ltd of China(2021420112000081)the Key Research and Development Program of Hubei Province(2020BAB084)the Program(BG20190227001)of High-end Foreign Experts of the State of the State Administration of Foreign Experts Affairs(SAFEA)。
文摘The nitrogen-doped carbon dots(N-CDs)were prepared by using coke powder as carbon source and one-step hydrothermal method.The N-CDs were studied as a fluorescent chemosensor for determining Cr(Ⅵ)in water.The selective,sensitive,reproducibility and stability of as-prepared N-CDs were investigated.The morphology,composition and properties of N-CDs were characterized by a series of methods.The fluorescence quenching of N-CDs by Cr(Ⅵ)was explored.The experimental results reveal that the obtained N-CDs have great hydrophilicity and strong luminescence properties,which demonstrates the successful doping of nitrogen into the CDs.The surface-active groups and emission wavelength range of CDs increase due to the electronegativity and electron donor effect of doping N atom.Furthermore,the N-CDs exhibit good photochemical properties for the detection of Cr(Ⅵ),including a wide linear range from 0.3 to 200μM(R^(2)=0.9935)and a low detection limit of 0.10μM at the signal-to-noise ratio of 3(S/N=3).Moreover,the N-CDs as a sensor was used successfully for Cr(Ⅵ)detection in real water samples with recovery rates of 99.9%-110.6%.This sensor also shows highly reproducibility and stability.The N-CDs fluorescent chemical sensor may be a potential candidate for applying in the field of other fluorescent chemical sensing,catalysis,photoelectric devices and other fields.
基金We acknowledge support from the equipment research and development projects of the Chinese Academy of Sciences,“On-chip integrated optical biochemical detection key technology research and development team,”E11YTB1001.
文摘In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluorescent indicator,a flow-focusing channel for generating droplets in oil,and a long storage channel for incubating and detecting the droplets.By monitoring the fluorescence intensity of the droplets,the device could detect changes in solution accurately over time.The chip can generate droplets at frequencies of up to 42 Hz with a mixing ratio of 1:1 and a temporal resolution of 3–6 s.It had excellent linearity in detecting fluorescein solution in the concentration range 1–5μM.This droplet microfluidic chip provides several advantages over traditional methods,including high temporal resolution,stable droplet generation,and faster flow rates.This approach could be applied to monitoring calcium ions with a dynamic range from 102 to 107 nM and a detection limit of 10 nM.
基金National Key R&D Program of China,Grant/Award Number:2022YFA1505900National Natural Science Foundation of China,Grant/Award Numbers:22105016,22173006+1 种基金Open Fund of Guangdong Provincial Key Laboratory of Luminescence,South China University of Technology,Grant/Award Number:2019B030301003Beijing Natural Science Foundation,Grant/Award Number:2222027。
文摘Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing on organic FNPs has not been achieved to date.Herein,we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene-based bis-ureidopyrimidinone monomers(bis-UPys)to relate the size to the fluorescence of organic nanoparticles.At an equal concentration of bis-UPys,a logarithmic relationship between them is built with a correlation coefficient higher than 0.96.Theoretical calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the nanoparticles.This leads to different nonradiative decay rates of the embedded and exposed bis-UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface areas.The established fluorescence intensity-size correlation possesses fine universality and reliability,and it is successfully utilized to estimate the sizes of other nanoparticles,including those in highly diluted dispersions of FNPs.This work paves a new way for the simple and real-time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.
基金supported by the National Natural Science Foundation of China(Nos.22175019 and 52002007)the Fundamental Research Funds for the Central Universitiesthe Youth Teacher International Exchange&Growth Program(No.QNXM20220019).
文摘Ti_(2)C quantum dots(QDs)with rich surface functional groups have been synthesized using a hydrothermal method,and used to detect tetracycline(Tc)based on enhanced fluorescence.The interaction between the surface functional groups of Ti_(2)C QDs and Tc enhanced the fluorescence of Tc at 514 nm,which is used to detect Tc quickly and accurately.Under optimal conditions,the fluorescence intensity was linear to the concentration of Tc in the range of 50.0–30.0μM,with a detection limit of 21.6 nM.Furthermore,the Tc-Ti_(2)C QDs detection system was evaluated for detection of Tc in milk and artificial urine.This study demonstrates a new and simple strategy for Tc detection,which is important for food safety and human health.
文摘Tadalafil(TAD)and dapoxetine HCl(DAP)are recently co-formulated and both show native fluorescence.Therefore,a novel,accurate,specific and sensitive reversed-phase high performance liquid chromatographic method with fluorescence detection was developed and validated for their separation and quantitation in dosage form and human plasma using avanafil as an internal standard(IS).Separation was achieved using isocratic elution within 7.0 min on C18column and acetonitrile-0.15%triethylamine(40∶60,v/v;pH 4)as a mobile phase.The flow rate was 1.0 mL/min and the detection was time-programmed at 330,410 and 370 nm for TAD,DAP and IS,respectively,after excitation at 236 nm.The linear ranges from 0.01 to 30.00μg/mL for each drug with the limits of detection of 4.20 and 7.20 ng/mL for TAD and DAP,respectively.The method was validated in accordance to the International Conference on Harmonization(ICH)guidelines and was successfully applied to spiked human plasma with mean recoveries of 98.17%and 98.83%for TAD and DAP respectively.
文摘Microbial activity in the water injection system in oil and gas industry leads to an array of challenges, including biofouling, injectivity loss, reservoir plugging, and microbiologically influenced corrosion (MIC). An effective mitigation strategy requires online and real-time monitoring of microbial activity and growth in the system so that the operators can apply and adjust counter-measures quickly and properly. The previous study [1] identified DNA staining technology-with PicoGreen and SYBR Green dyes—as a very promising method for automated, online determination of microbial cell abundance in the vast Saudi Aramco injection seawater systems. This study evaluated DNA staining technology on detection limit, automation potential, and temperature stability for the construction of automated sensor prototype. DNA staining with SYBR Green dye was determined to be better suited for online and real-time monitoring of microbial activity in the Saudi Aramco seawater systems. SYBR Green staining does not require sample pre-treatment, and the fluorescence signal intensity is more stable at elevated temperatures up to 30℃. The lower detection limit of 2 × 10<sup>3</sup>/ml was achieved under the optimized conditions, which is sufficient to detect microbial numbers in Saudi Aramco injection seawater. Finally, the requirements for design and construction of SYBR-based automated sensor prototype were determined.
文摘Microbial activity is the cause of a variety of problems in water injection systems, e.g., microbial corrosion, plugging, and biofouling. Efficient monitoring of Saudi Aramco’s vast water injection system requires the development of online and automated technologies for monitoring microbial activities in the system. A previous system review and technology screening has identified five single-analyte strategies [1], which were evaluated in this study with a laboratory-scale setup to determine their applicability for automated determination of microbial activity in the injection water system. Four of the five single-analyte measuring principles tested in the laboratory setup were deemed less suitable for automation and/or reliable for use in the detection of microbial activity in the company injection water system. These four principles were: luminescence assay for adenosine-5’-triphosphate (ATP), detection and electrochemical measurements of H<sub>2</sub>S, determination of pH by electrochemical sensor, and measurement of oxidation-reduction potential (ORP). The strategy of staining cells with fluorescent DNA dyes, followed by quantification of fluorescence signals, was identified to hold, with proper optimization of DNA staining and fluorescence detection, a very promising potential for integration in automated, online sensors for microbial activity in the injection water system.
基金supported by the National Natural Science Foundation of China(Nos.22171100,22288101)and the“111”Project of China(No.B17020).
文摘Anovel metal-organic framework{[In_(3)(TATAT)_(2)]·3CH_(3)NH_(3)·7NMF·8H_(2)O}[JLU-MOF101,H_(6)TATAT=5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris-(azanediyl)triisophthalate,NMF=N-methyl-formamide]with cor topology has been synthesized under solvothermal conditions.The framework of JLU-MOF101 is constructed by{In(COO)_(4)}-nodes and a hexacarboxylic organic ligand.JLU-MOF101 exhibits excellent fluorescence properties in N,N-dimethylformamide(DMF)solution,and its emission spectrum can be greatly overlapped with the ultraviolet absorption spectra of trinitrophenol(TNP)and 2,4-dinitrophenol(2,4-DNP).As a result,JLU-MOF101 exhibits excellent performance of fluorescence quenching for TNP and 2,4-DNP.In addition,we demonstrate the selective detection capability of JLU-MOF101 through a large number of anti-interference tests.
基金the National Natural Science Foundation of China(Nos.21701015,61975214,21811530054,61671435)Beijing Natural Science Foundation(No.4202075)the National Key R&D Program(No.2018YFC0115500)。
文摘In this work,polymethacrylic acid(PMAA)-templated silver nanoclusters(Ag NCs)were developed as the fluorescent probe for the efficient and sensitive detection of adenosine triphosphate(ATP)in a wide range of pH values.The fluorescence intensity of the Ag NCs could keep stable with pH values ranging from2.5 to 9.3.The detection of ATP was based on the quenching of the fluorescent Ag NCs in the presence of ATP.The fluorescence quenching of the Ag NCs with increasing ATP concentration was studied at pH 2.5,4.5,7.0 and 8.5 which involved a wide pH environment in body fluids.The limit of detection(LOD)for ATP was as low as 0.1 mmol/L in an acidic environment with pH of 2.5 and all the linear correlation coefficients were satisfactory under wide-span pH values from 2.5 to 8.5.In addition,the sensitive determination of ATP was also achieved by adding copper ions(Cu^2+).The high selectivity and rapid detection process proved that the fluorescent probe had great potential to detect ATP in biological samples under different pH conditions.
基金supported by the National Natural Science Foundation of China(22074005)the Natural Science Foundation of Beijing Municipality(2202038)the Open Research Fund Program of Beijing Key Lab of Plant Resource Research and Development,Beijing Technology and Business University(PRRD-2021-YB6)
文摘Formaldehyde(FA,a typical reactive carbonyl species)is a well-known environmental pollutant and a disease-related biomarker,making its sensitive and selective detection significant.Fluorescent probes have been explored for FA perception in environment,intracellular media and in vivo.In this review,we majorly conclude the recently represented fluorescence FA analysis based on small molecule probes.The general FA sensing mechanisms are first introduced.Regarding the FA detection in various environments,sensing tactics and performances are discussed in order of natural environment,living cells and in vivo.In the end,this review discusses the challenges and future trends of FA detection based on fluorescent probes.
