In this work,molybdenum disulfide quantum dots（MoS2 QDs） were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nan...In this work,molybdenum disulfide quantum dots（MoS2 QDs） were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nanosheets into MoS2 QDs solution,they produced an obvious fluorescence quenching,which should be due to inner filter effect（IFE）.Meanwhile,the fluorescent probe was formed,Interestingly,we found that this quenching phenomenon disappeared with the addition of ascorbic acid,In other words,the fluorescence gradually restored.This recovery phenomenon is mainly due to the reduction effect of ascorbic acid for MnO2 nanosheets.Under the optimum conditions,the limit of detection（LOD） of 39 nmol/L for ascorbic acid was achieved with a linear range of 0.33-5.00 μmol/L.The repeatability was better than 5.0% for ascorbic acid in both standard and fruit samples（n = 3）.Moreover,the as-fabricated fluorescent sensing system was successfully employed to detect the ascorbic acid levels in hawthorn and jujube with satisfactory results.展开更多
A molecularly imprinted electrochemical sensor was prepared based on poly folic acid（PFA） for rapid detection of barbital（BAR）. The PFA membrane was obtained via directly electropolymerization technique on the sur...A molecularly imprinted electrochemical sensor was prepared based on poly folic acid（PFA） for rapid detection of barbital（BAR）. The PFA membrane was obtained via directly electropolymerization technique on the surface of chemically modified Au electrode（Au/CME） by means of cyclic voltammetry（CV） in the potential range between-0.4 and 1.0 V in phosphate buffer solution（PBS） pH 7.04. The molecularly imprinted polymers（MIP） membrane was synthesized with BAR as template molecules and folic acid（FA） as the functional monomer. The performance and surface feature of the proposed imprinted sensor were investigated using CV, differential pulse voltammetry（DPV）, electrochemical impedance spectroscopy（EIS） and scanning electron microscope（SEM）. Under the optimized conditions, the peak current decrease（ΔIp） was proportional to the BAR concentration in the range of 1.00×10^-7-1.00×10^-4 mol/L（R^2=0.998 2） with a detection limit（S/N=3） of 4.65×10^-8 mol/L. The results indicated that the imprinted sensor exhibited an excellent selectivity for BAR and it was successfully used to determine BAR in real samples with recoveries of 94.7%-106.2% by using the standard addition method.展开更多
A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accu...A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accuracy wee investigated. The experimental results indicate that the analytical performance of the sensor is satisfactory.展开更多
Sensors capable of recognizing cell surface carbohydrates,such as sialyl Lewis X（sLe-x）,are invaluable research tools and for the diagnosis and early detection of many forms of cancer.In this paper,we report the des...Sensors capable of recognizing cell surface carbohydrates,such as sialyl Lewis X（sLe-x）,are invaluable research tools and for the diagnosis and early detection of many forms of cancer.In this paper,we report the design and synthesis of a series of bisboronic acids 6（a-f） as fluorescent sensors towards mono-/oligosaccharides.Among them,compounds 6d and 6e showed strong binding affinities with glucose and fructose,while compound 6c,in which two anthracene-based boronic acid units were linked by a hexamethylene spacer,was able to recognize sLe-x selectivity and stained HEPG2 cells at 1 μmoI/L.展开更多
Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for...Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for the detection of deoxyribonucleic acid （DNA） hybridization. The Au-gated AIInN/GaN HEMT biosensor exhibits higher sensitivity in comparison with the AlGaN/GaN HEMT biosensor. For the former, the drain-source current （VDS = 0.5 V） shows a clear decrease of 69μA upon the introduction of 1μmolL^-1 （μM） complimentary DNA to the probe DNA at the sensor area, while for the latter it is only 38 μA. This current reduction is a notable indication of the hybridization. The high sensitivity can be attributed to the thinner barrier of the AlInN/GaN heterostructure, which makes the two-dimensional electron gas channel more susceptible to a slight change of the surface charge.展开更多
An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)stud...An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)studies indicated that unsymmetrical N,O-chelated BF2complexes were highly fluorescent in solid state,and exhibited large Stokes shifts,excellent photostability,along with insensitivity to p H.Theα-aryl group could not only modulate the electronic effect but also inhibit the intermolecularπ-πstacking to promote the aggregation-induced emission(AIE)effect.DFT calculations and experiments identified that the intramolecular charge transfer properties of these N,O-chelates could be switched by the modification of substituents,resulting tunable fluorescence wavelengths.Furthermore,post-complexation modification was accomplished,including Suzuki-Miyaura cross-coupling,Buchwald-Hartwig amination,oxidative cleavage,along with a unique triple substitution reaction involving propargyl Grignard reagents.The exemplificative application of dimethylamine substituted boron complex as a reversible acidic vapor sensor was also demonstrated.展开更多
Large π-conjugated pyrene-phenazine monoimide and bisimides were synthesized by imine condensation reaction. These imides form well ordered 1D nanotapes upon self-assembly in solution. Electrochemical and electric co...Large π-conjugated pyrene-phenazine monoimide and bisimides were synthesized by imine condensation reaction. These imides form well ordered 1D nanotapes upon self-assembly in solution. Electrochemical and electric conductivity measurement reveal it can be served as an n-channel semiconductor with large charge carrier mobility up to 4.1 cm^2 V^-1 s^-1. Both alkylated imides are highly luminescent, and can be quenched via protonization using trifluoroacetic acid, which could be served as potential colorimetric acid sensors.展开更多
A sensitive and selective method for the determination of ascorbic acid（AA） using [Cu（phen）2]2＋/multiwalled carbon nanotubes modified glassy carbon electrode was developed. Electrochemical behavior and surface ch...A sensitive and selective method for the determination of ascorbic acid（AA） using [Cu（phen）2]2＋/multiwalled carbon nanotubes modified glassy carbon electrode was developed. Electrochemical behavior and surface characteristics of the modified electrode were studied using scanning electrode microscopy（SEM）, electrochemical impedance spectroscopy（EIS） and cyclic voltammetry（CV）. The experimental results showed that the modified electrode enhanced the electrochemical response of AA and exhibited good analytical performance for AA determination from 10 to 1 042 ？mol/L with a low detection limit of 9.67μmol/L（S/N=3）. The modified electrode was also applied to the determination of AA in the Vitamin tablets and showed good recovery.展开更多
Ni^（2＋）-doped ZnO nanorods with different doping concentrations are prepared via the solvothermal method.The doped ZnO nanorods are characterized by X-ray diffraction（XRD） and scanning electron microscopy （SEM）...Ni^（2＋）-doped ZnO nanorods with different doping concentrations are prepared via the solvothermal method.The doped ZnO nanorods are characterized by X-ray diffraction（XRD） and scanning electron microscopy （SEM）,respectively.The amount of Ni^（2＋） ions that enter the lattice of ZnO increases with increasing the Ni^（2＋）/Zn^（2＋） molar ratio when the molar ratio of Ni^（2＋）/Zn^（2＋） in the starting solution is lower than 3%and does not change obviously if the mole ratio of Ni^（2＋）/Zn^（2＋） in the starting solution is in the range of 3-10 mol%.The effect of Ni^（2＋） doping on the gas-sensing properties is investigated.The results reveal that the amount of Ni^（2＋） has a great influence on the response（R_a/R_g） and the gas-sensing selectivity.The sensor based on 1 mol%Ni^（2＋） doped ZnO nanorods （120℃,10 h） exhibits a high response to acetic acid vapor,in particular,the responses to 0.001 ppm and 0.01 ppm acetic acid vapor reach 1.6 and 2,respectively.The response time and the recovery time for 0.001 ppm acetic acid are only 4 s and 27 s,respectively.展开更多
A piezoelectric nucleic acid sensor was constructed for detection of tumor necrosis factor gene.Two methods were employed for immobilization of nucleic acid probe on gold electrode of piezoelectric crystal.The results...A piezoelectric nucleic acid sensor was constructed for detection of tumor necrosis factor gene.Two methods were employed for immobilization of nucleic acid probe on gold electrode of piezoelectric crystal.The results show that polyethyleneimine adhesion and glutaraldehyde cross-linking method has higher sensitivity,stability and selectivity than protein A method.The solid-phase nucleic acid hybridization of oligo nucleotides and tumor necrosis factor target gene sequence were monitored using this sensor.Tumor necrosis factor gene sequence(580 bp)was detected by this nucleic acid sensor for the first time.展开更多
From the conventional knowledge of protein nutrition to the molecular nutrition of amino acids, our understanding of protein/amino acid nutrition is rapidly increasing. Amino acids control cell growth and metabolism t...From the conventional knowledge of protein nutrition to the molecular nutrition of amino acids, our understanding of protein/amino acid nutrition is rapidly increasing. Amino acids control cell growth and metabolism through two amino acid-sensingpathways, i.e. target of rapamycin complex 1 (TORC1) and the general control nonderepressible 2 (GCN2) signaling pathway.In the amino acid-abundant status, TORC1 dominates intracellular signaling and increases protein synthesis and cell growth.In contrast, amino acid deprivation actives GCN2 resulting in repression of general protein synthesis but facilitates the aminoacid transport and synthesis process. By integrating and coordinating nutrition and hormone signaling, TORC1 and GCN2control the switch of the catabolism and anabolism phase in most eukaryotes. Now, we appreciate that the availability ofindividual amino acids is sensed by intracellular sensors. These cutting-edge findings expand our knowledge of amino acidnutrition. Although the TORC1 and GCN2 were discovered decades ago, the study of molecular amino acid nutrition inaquaculture animals is still at its infancy. The aquaculture industry is highly dependent on the supply of fishmeal, which isthe major protein source in aquacultural animal diets. Some concerted efforts were conducted to substitute for fishmeal dueto limited supply of it. However, the concomitant issues including the unbalanced amino acid profile of alternative proteinsources limited the utilization of those proteins. Continued study of the molecular nutrition of amino acid in aquacultureanimals may be expected in the immediate future to expand our knowledge on the utilization of alternative protein sources.展开更多
Recognition behavior of a hexaazatriphenylene （HAT） derivative toward different acids in THF solution was investigated through EH NMR, UV-vis and fluorescence spectroscopic experiments, as well as SEM image and semi...Recognition behavior of a hexaazatriphenylene （HAT） derivative toward different acids in THF solution was investigated through EH NMR, UV-vis and fluorescence spectroscopic experiments, as well as SEM image and semi-empirical calculations, which revealed that this propeller-like HAT receptor could co-assemble into a layered complex by sandwiching protons and halogen （chloride or bromide） anions synergistically between the receptor molecules. What＇s more, reversible and remarkable color changes visible to the naked eye could be observed, when the halogen acid and base were introduced alternatively.展开更多
基金financially supported by National Nature Science Foundation of China (No. 21475053)
文摘In this work,molybdenum disulfide quantum dots（MoS2 QDs） were firstly prepared by hydrothermal method using sodium molybdate and glutathione as precursors,and applied in ascorbic acid detection.When joining MnO2 nanosheets into MoS2 QDs solution,they produced an obvious fluorescence quenching,which should be due to inner filter effect（IFE）.Meanwhile,the fluorescent probe was formed,Interestingly,we found that this quenching phenomenon disappeared with the addition of ascorbic acid,In other words,the fluorescence gradually restored.This recovery phenomenon is mainly due to the reduction effect of ascorbic acid for MnO2 nanosheets.Under the optimum conditions,the limit of detection（LOD） of 39 nmol/L for ascorbic acid was achieved with a linear range of 0.33-5.00 μmol/L.The repeatability was better than 5.0% for ascorbic acid in both standard and fruit samples（n = 3）.Moreover,the as-fabricated fluorescent sensing system was successfully employed to detect the ascorbic acid levels in hawthorn and jujube with satisfactory results.
基金Supported by the Natural Science Foundation of Shanxi Province(20001057)
文摘A molecularly imprinted electrochemical sensor was prepared based on poly folic acid（PFA） for rapid detection of barbital（BAR）. The PFA membrane was obtained via directly electropolymerization technique on the surface of chemically modified Au electrode（Au/CME） by means of cyclic voltammetry（CV） in the potential range between-0.4 and 1.0 V in phosphate buffer solution（PBS） pH 7.04. The molecularly imprinted polymers（MIP） membrane was synthesized with BAR as template molecules and folic acid（FA） as the functional monomer. The performance and surface feature of the proposed imprinted sensor were investigated using CV, differential pulse voltammetry（DPV）, electrochemical impedance spectroscopy（EIS） and scanning electron microscope（SEM）. Under the optimized conditions, the peak current decrease（ΔIp） was proportional to the BAR concentration in the range of 1.00×10^-7-1.00×10^-4 mol/L（R^2=0.998 2） with a detection limit（S/N=3） of 4.65×10^-8 mol/L. The results indicated that the imprinted sensor exhibited an excellent selectivity for BAR and it was successfully used to determine BAR in real samples with recoveries of 94.7%-106.2% by using the standard addition method.
文摘A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accuracy wee investigated. The experimental results indicate that the analytical performance of the sensor is satisfactory.
基金supported by the National Natural Science Foundation of China(NSFC)(No.21372060)Hebei Province Natural Science Fund for Distinguished Young Scholars(No.B2015201005)
文摘Sensors capable of recognizing cell surface carbohydrates,such as sialyl Lewis X（sLe-x）,are invaluable research tools and for the diagnosis and early detection of many forms of cancer.In this paper,we report the design and synthesis of a series of bisboronic acids 6（a-f） as fluorescent sensors towards mono-/oligosaccharides.Among them,compounds 6d and 6e showed strong binding affinities with glucose and fructose,while compound 6c,in which two anthracene-based boronic acid units were linked by a hexamethylene spacer,was able to recognize sLe-x selectivity and stained HEPG2 cells at 1 μmoI/L.
基金Supported by the National Key Research and Development Program of China under Grant Nos 2016YFB0400104 and2016YFB0400301the National Natural Sciences Foundation of China under Grant No 61334002the National Science and Technology Major Project
文摘Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for the detection of deoxyribonucleic acid （DNA） hybridization. The Au-gated AIInN/GaN HEMT biosensor exhibits higher sensitivity in comparison with the AlGaN/GaN HEMT biosensor. For the former, the drain-source current （VDS = 0.5 V） shows a clear decrease of 69μA upon the introduction of 1μmolL^-1 （μM） complimentary DNA to the probe DNA at the sensor area, while for the latter it is only 38 μA. This current reduction is a notable indication of the hybridization. The high sensitivity can be attributed to the thinner barrier of the AlInN/GaN heterostructure, which makes the two-dimensional electron gas channel more susceptible to a slight change of the surface charge.
基金grateful for the support by the National Natural Science Foundation of China(Nos.21702013,22271010)。
文摘An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)studies indicated that unsymmetrical N,O-chelated BF2complexes were highly fluorescent in solid state,and exhibited large Stokes shifts,excellent photostability,along with insensitivity to p H.Theα-aryl group could not only modulate the electronic effect but also inhibit the intermolecularπ-πstacking to promote the aggregation-induced emission(AIE)effect.DFT calculations and experiments identified that the intramolecular charge transfer properties of these N,O-chelates could be switched by the modification of substituents,resulting tunable fluorescence wavelengths.Furthermore,post-complexation modification was accomplished,including Suzuki-Miyaura cross-coupling,Buchwald-Hartwig amination,oxidative cleavage,along with a unique triple substitution reaction involving propargyl Grignard reagents.The exemplificative application of dimethylamine substituted boron complex as a reversible acidic vapor sensor was also demonstrated.
基金supported by the National Natural Science Foundation of China(Nos. 51522303, 21602154)National Key R&D Program of China (No. 2017YFA0207500)the Thousand Youth Talents Plan
文摘Large π-conjugated pyrene-phenazine monoimide and bisimides were synthesized by imine condensation reaction. These imides form well ordered 1D nanotapes upon self-assembly in solution. Electrochemical and electric conductivity measurement reveal it can be served as an n-channel semiconductor with large charge carrier mobility up to 4.1 cm^2 V^-1 s^-1. Both alkylated imides are highly luminescent, and can be quenched via protonization using trifluoroacetic acid, which could be served as potential colorimetric acid sensors.
基金Funded by the National Natural Science Foundation of China(No.51273155)the Fundamental Research Funds for the Central Universities(No.2012-Ia-022)
文摘A sensitive and selective method for the determination of ascorbic acid（AA） using [Cu（phen）2]2＋/multiwalled carbon nanotubes modified glassy carbon electrode was developed. Electrochemical behavior and surface characteristics of the modified electrode were studied using scanning electrode microscopy（SEM）, electrochemical impedance spectroscopy（EIS） and cyclic voltammetry（CV）. The experimental results showed that the modified electrode enhanced the electrochemical response of AA and exhibited good analytical performance for AA determination from 10 to 1 042 ？mol/L with a low detection limit of 9.67μmol/L（S/N=3）. The modified electrode was also applied to the determination of AA in the Vitamin tablets and showed good recovery.
基金supported by the National Natural Science Foundation of China(No.61271156)the Innovation Team Project of AHUT(No. TD201204)the Research Project for University Personnel Returning from Overseas Sponsored by the Ministry of Education of China
文摘Ni^（2＋）-doped ZnO nanorods with different doping concentrations are prepared via the solvothermal method.The doped ZnO nanorods are characterized by X-ray diffraction（XRD） and scanning electron microscopy （SEM）,respectively.The amount of Ni^（2＋） ions that enter the lattice of ZnO increases with increasing the Ni^（2＋）/Zn^（2＋） molar ratio when the molar ratio of Ni^（2＋）/Zn^（2＋） in the starting solution is lower than 3%and does not change obviously if the mole ratio of Ni^（2＋）/Zn^（2＋） in the starting solution is in the range of 3-10 mol%.The effect of Ni^（2＋） doping on the gas-sensing properties is investigated.The results reveal that the amount of Ni^（2＋） has a great influence on the response（R_a/R_g） and the gas-sensing selectivity.The sensor based on 1 mol%Ni^（2＋） doped ZnO nanorods （120℃,10 h） exhibits a high response to acetic acid vapor,in particular,the responses to 0.001 ppm and 0.01 ppm acetic acid vapor reach 1.6 and 2,respectively.The response time and the recovery time for 0.001 ppm acetic acid are only 4 s and 27 s,respectively.
基金supported by the National Natural Science Foundation of China(No.39670218)
文摘A piezoelectric nucleic acid sensor was constructed for detection of tumor necrosis factor gene.Two methods were employed for immobilization of nucleic acid probe on gold electrode of piezoelectric crystal.The results show that polyethyleneimine adhesion and glutaraldehyde cross-linking method has higher sensitivity,stability and selectivity than protein A method.The solid-phase nucleic acid hybridization of oligo nucleotides and tumor necrosis factor target gene sequence were monitored using this sensor.Tumor necrosis factor gene sequence(580 bp)was detected by this nucleic acid sensor for the first time.
文摘From the conventional knowledge of protein nutrition to the molecular nutrition of amino acids, our understanding of protein/amino acid nutrition is rapidly increasing. Amino acids control cell growth and metabolism through two amino acid-sensingpathways, i.e. target of rapamycin complex 1 (TORC1) and the general control nonderepressible 2 (GCN2) signaling pathway.In the amino acid-abundant status, TORC1 dominates intracellular signaling and increases protein synthesis and cell growth.In contrast, amino acid deprivation actives GCN2 resulting in repression of general protein synthesis but facilitates the aminoacid transport and synthesis process. By integrating and coordinating nutrition and hormone signaling, TORC1 and GCN2control the switch of the catabolism and anabolism phase in most eukaryotes. Now, we appreciate that the availability ofindividual amino acids is sensed by intracellular sensors. These cutting-edge findings expand our knowledge of amino acidnutrition. Although the TORC1 and GCN2 were discovered decades ago, the study of molecular amino acid nutrition inaquaculture animals is still at its infancy. The aquaculture industry is highly dependent on the supply of fishmeal, which isthe major protein source in aquacultural animal diets. Some concerted efforts were conducted to substitute for fishmeal dueto limited supply of it. However, the concomitant issues including the unbalanced amino acid profile of alternative proteinsources limited the utilization of those proteins. Continued study of the molecular nutrition of amino acid in aquacultureanimals may be expected in the immediate future to expand our knowledge on the utilization of alternative protein sources.
基金The authors are gratet＇ul to tile National Natural Science Foundation of China （Nos. 21502216, 21602205） and the Zhejiang Normal University for financial support.
文摘Recognition behavior of a hexaazatriphenylene （HAT） derivative toward different acids in THF solution was investigated through EH NMR, UV-vis and fluorescence spectroscopic experiments, as well as SEM image and semi-empirical calculations, which revealed that this propeller-like HAT receptor could co-assemble into a layered complex by sandwiching protons and halogen （chloride or bromide） anions synergistically between the receptor molecules. What＇s more, reversible and remarkable color changes visible to the naked eye could be observed, when the halogen acid and base were introduced alternatively.
