This paper presents the studying results of the sodium ion sensor device based on the SnO_2/ITO glass structure in the detection of rinsing solution for contact lenses.The selective membrane contains poly (vinyl chlor...This paper presents the studying results of the sodium ion sensor device based on the SnO_2/ITO glass structure in the detection of rinsing solution for contact lenses.The selective membrane contains poly (vinyl chloride) (PVC),bis (2-ethylhexyl) sebacate (DOS),(12-crown-4) methylmalonate (B12C4),and sodium tetrakis (4-fluoropbenyl) borate dehydrate (NaTFBD). The final weight ratios are PVC:DOS:B12C4:NaTFBD=33:66:2:2.In this condition,the sensor has performances with linear sensitivity,short response time,good repeatability and selectivity.The sensor was used to measure the rinsing solution for the contact lenses.Because the experimental results show close to the accurate value for four commercial products,this sensor can preliminary be used in detecting the rinsing solution for the contact lenses.Using this structure and sodium-sensing membrane to construct the sodium sensor is proven successfully in this application.展开更多
A cobalt-iron alloy thin-film electrode-based electrochemical hydrogen-phosphate-ion sensor was prepared by electrodepositing on an Au-coated Al2O3 substrate from an aqueous solution of metal-salts. The use of a cobal...A cobalt-iron alloy thin-film electrode-based electrochemical hydrogen-phosphate-ion sensor was prepared by electrodepositing on an Au-coated Al2O3 substrate from an aqueous solution of metal-salts. The use of a cobalt-iron alloy electrode greatly improved the hydrogen-ion sensor response performance, i.e., the sensor worked stably for more than 7 weeks and showed a quick response time of several seconds. Among the cobalt and iron alloy systems tested, the electrodeposited Co58Fe42 thin-film electrode showed the best EMF response characteristics, i.e., the sensor exhibited a linear potentiometric response to hydrogen-phosphate ion at the concentration range between 1.0 × 10–5 and 1.0 × 10–2 M with the slope of –43 mV/decade at pH 5.0 and at 30℃. A sensing mechanism of the Co-based potentiometric hydrogen-phosphate ion sensor was proposed on the basis of results of instrumental analysis.展开更多
Real-time monitoring of ion content variations in humans offers a noninvasive approach to ensuring health,made possible through wearable sensors.However,challenges such as the low capacitance of the solid-contact(SC)l...Real-time monitoring of ion content variations in humans offers a noninvasive approach to ensuring health,made possible through wearable sensors.However,challenges such as the low capacitance of the solid-contact(SC)layer and the formation of a water layer hinder the low-concentration ion detection and stable performance of these sensors.To address these limitations,a novel design is proposed using graphene quantum dots(GQD)-doped polypyrrole(PPy)nano-dendritic membranes,combined with a hydrophobic Nafion membrane,for sweat ion sensors.The GQD-doped PPy membrane serves as the SC layer,where GQD enhance capacitance and the nano-dendritic structure improves ion-to-electron transduction efficiency.Meanwhile,the hydrophobic Nafion membrane prevents water layer formation,stabilizing the sensor's performance.This design significantly improves both the sensitivity(from 49 m V/decade to 70 m V/decade)and stability(potential drift decreasing from 1.3 m V/h to18.7μV/h)of the sensor.Leveraging this configuration,Na^(+)and K^(+)sensors are integrated onto a flexible electrode using a dispense-coupled inkjet printing technique.This enables real-time,continuous monitoring of Na^(+)and K^(+) concentrations in human sweat simultaneously.The proposed sensing device demonstrates strong potential for noninvasive sweat monitoring,contributing to enhanced health management in daily life.展开更多
Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmi...Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmium ions(Cd(Ⅱ)).In this study,we present a novel screen-printed carbon electrode(SPCE)modified with single crystallineα-Fe_(2)O_(3)nano-hexagons that functions as a sensor for detecting Cd(Ⅱ).The performance of the fabricated sensor was thoroughly assessed and compared with unmodified SPCE using the voltammetric method.The crystalline structure of the synthesizedα-Fe_(2)O_(3)nano-hexagons was confirmed through XRD,and surface analysis revealed an average diameter and thickness of 86 nm and 9 nm,respectively.Theα-Fe_(2)O_(3)modified SPCE yields a 7-fold enhanced response(at pH 5.0 vs.Ag/AgCl)to Cd(Ⅱ)than bare SPCE.The modified electrode effectively detects Cd(Ⅱ)with a linear response range of up to 333.0μmol/L and a detection limit of 0.65 nmol/L under ideal circumstances.This newly fabricated sensor offers significant potential for environmental monitoring applications by providing outstanding practicality,anti-interference ability,and repeatability for detecting Cd(Ⅱ)in water samples.展开更多
Conductive inks based on graphene materials have received significant attention for the fabrication of a wide range of printed and flexible devices.However,the application of graphene fillers is limited by their restr...Conductive inks based on graphene materials have received significant attention for the fabrication of a wide range of printed and flexible devices.However,the application of graphene fillers is limited by their restricted mass production and the low concentration of their suspensions.In this study,a highly concentrated and conductive ink based on defect-free graphene was developed by a scalable fluid dynamics process.A high shear exfoliation and mixing process enabled the production of graphene at a high concentration of 47.5 mg mL^(−1)for graphene ink.The screen-printed graphene conductor exhibits a high electrical conductivity of 1.49×10^(4)S m^(−1)and maintains high conductivity under mechanical bending,compressing,and fatigue tests.Based on the as-prepared graphene ink,a printed electrochemical sodium ion(Na^(+))sensor that shows high potentiometric sensing performance was fabricated.Further,by integrating a wireless electronic module,a prototype Na^(+)-sensing watch is demonstrated for the real-time monitoring of the sodium ion concentration in human sweat during the indoor exercise of a volunteer.The scalable and efficient procedure for the preparation of graphene ink presented in this work is very promising for the low-cost,reproducible,and large-scale printing of flexible and wearable electronic devices.展开更多
An electrochemical sensor based on self-made nano-porous pseudo carbon paste electrode(nano-PPCPE)has been successfully developed,and used to detect Cd^2+ and Pb^2+.The experimental results showed that the electrochem...An electrochemical sensor based on self-made nano-porous pseudo carbon paste electrode(nano-PPCPE)has been successfully developed,and used to detect Cd^2+ and Pb^2+.The experimental results showed that the electrochemical performance of nanoPPCPE is evidently better than both glassy carbon electrode(GCE)and pure carbon paste electrode(CPE).Then the prepared nano-PPCPE was applied to detect Cd^2+ and Pb^2+in standard solution,the results showed that the electrodes can quantitatively detect trace Cd^2+ and Pb^2+,which has great significance in electrochemical analysis and detection.The linear ranges between the target ions concentration and the D PASV current were from 0.1-3.0 μmol/L,0.05-4.0 μmol/L for Cd^2+ and Pb^2+,respectively.And the detection limits were 0.0780 μmol/L and 0.0292 μmol/L,respectively.Moreover,the preparation of the nano-PPCPE is cheap,simple and has important practical value.展开更多
A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of the...A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of these pillar[5]arene-based pseudorotaxanes and polypseudorotaxanes occurred upon the addition of Cl,Br,and I（tetrabutylammonium salts）,respectively,leading to their fluorescence recovery.The fluorescence enhancement of the pseudorotaxane and the polypseudorotaxanes increases in the order of I展开更多
CdSe/CdS quantum dots （QDs） functionalized by thiourea （TU） were synthesized and used as a fluorescent sensor for mercury ion detection. The TU-functionalized QDs were prepared by bonding TU via electrostatic inte...CdSe/CdS quantum dots （QDs） functionalized by thiourea （TU） were synthesized and used as a fluorescent sensor for mercury ion detection. The TU-functionalized QDs were prepared by bonding TU via electrostatic interaction to the core/shell CdSe/CdS QDs after capping with thioglycolic acid （TGA）. It was observed that the fluorescence of the functionalized QDs was quenched upon the addition of Hg^2＋. The quantitative detection of Hg^2＋ with this fluorescent sensor could be conducted based on the linear relationship between the extent of quenching and the concentration of Hg^2＋ added in the range of 1-300 μg.L^-1, A detection limit of 0.56 μg.L^-1 was achieved. The sensor showed superior selectivity for Hg^2＋ and was successfully applied to the determination of mercury in environmental samples with satisfactory results展开更多
A novel and simple fluorescent molecular sensor,1-pyrenecarboxaldehyde thiosemicarbazone（Hpytsc）,was synthesized.Its higher sensitivity and selectivity to mercury（Ⅱ） ion were studied through absorption and emissi...A novel and simple fluorescent molecular sensor,1-pyrenecarboxaldehyde thiosemicarbazone（Hpytsc）,was synthesized.Its higher sensitivity and selectivity to mercury（Ⅱ） ion were studied through absorption and emission channels.The UV-vis spectra show that the increasing mercury（Ⅱ） ion concentrations result in the decreasing absorption intensity.The fluorescence monomer emission of Hpytsc is enhanced upon binding mercury（Ⅱ） ion,which should be due to the 1：1 complex formation between Hpytsc and metal ion.展开更多
In this study,a new Er^3＋ sensor based on N-（benzyloxycarbonyloxy）succinimide（BCS） as a neutral carrier has been constructed. The sensor exhibits potential linear response with a Nernstian slope of 20.5±0.4 ...In this study,a new Er^3＋ sensor based on N-（benzyloxycarbonyloxy）succinimide（BCS） as a neutral carrier has been constructed. The sensor exhibits potential linear response with a Nernstian slope of 20.5±0.4 mV/decade in the concentration range of 1.0×10^-6to 1.0×10^-2mol/L of Er^3＋.It has a very short response time（10 s）,detection limit of 6.3×10^-7 mol/L and a good selectivity relative to a wide variety of other metal ions including common alkali,alkaline earth,heavy,and transition metal ions.It can be used in the pH range of 2.5-10.6 without any considerable divergence in potentials.The proposed sensor was successfully applied for the recovery of Er^3＋ ions spiked in tap and river water samples.展开更多
A highly efficient coupling reaction of N-heterocyclic carbene precursors with sulfonyl azides has been developed, affording a variety of pyrido[1,2-c][1,2,4]triazole-based π-conjugated triazenes. The present reactio...A highly efficient coupling reaction of N-heterocyclic carbene precursors with sulfonyl azides has been developed, affording a variety of pyrido[1,2-c][1,2,4]triazole-based π-conjugated triazenes. The present reaction proceeds under very mild conditions with good functional group tolerance. The resulting triazenes exhibit selective and sensitive fluorescent response toward Fe3+ion.展开更多
In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixe...In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixels. Using gastric tissues prepared from the stomach, pH distribution was observed during the histamine stimulation. The 2D distribution of [pH]out in the gastric tissues showed clear differences between the mucosal sides and the serous side. Even before the histamine stimulation, the mucosal side of the gastric mucosa showed a slightly lower pH than that of serous side. In the mucosal side, [pH]out decreased after the onset of the stimulation. The ion image sensor was capable of visualizing [pH]out in the gastric tissues. The present chemical-sensing technique realized a label-free microscopic assessment of the 2D distributions of biologically interesting substances, and consequently, [pH] out imaging via chemical microscopy has a future potential in medical fields for endoscopic analysis of gastric ulcers.展开更多
An electrochemical sensor incorporating a signal enhancement for the determination of lead （II） ions （Pb2＋） was designed on the basis of the thrombin-binding aptamer （TBA） as a molecular recog- nition element a...An electrochemical sensor incorporating a signal enhancement for the determination of lead （II） ions （Pb2＋） was designed on the basis of the thrombin-binding aptamer （TBA） as a molecular recog- nition element and ionic liquid supported cerium oxide （CeO2） nanoparticles-carbon nanotubes compo- site modification. The composite comprises nanoparticles CeO2, multi-waU carbon nanotubes （MWNTs） and hydrophobic room temperature ionic liquid （RTIL） 1-ethyl-3-methylimidazolium tetrafluoroborate （EMIMBF4）. The electrochemical sensors were fabricated by immersing the CeOa-MWNTs-EMIMBF4 modified glassy carbon electrode （GCE） into the solution of TBA probe. In the presence of Pb2＋, the TBA probe could form stable G-quartet structure by the specific binding interactions between Pb2＋ and TBA. The TBA-bound Pb2＋ can be electrochemically reduced, which provides a readout signal for quantitative detection of Pb2＋. The reduction peak current is linearly related to the concentration of Pb2＋ from 1.0 ＊ 10-8 M to 1.0 ＊ 105 M with a detection limit of 5 ＊ 109 M. This work demonstrates that the CeOz-MWNTs-EMIMBF4 nanocomposite modified GCE provides a promising platform for immobi- lizing the TBA probe and enhancing the sensitivity of the DNA-based sensors.展开更多
In this work a new Lu^（3＋） PVC-membrane sensor based on 2,2＇-dithiobis（4-methylthiazole）（TMT） has been fabricated.The sensor exhibits a Nernstian slope of 19.6±0.4 mV decade（？） in the concentration ran...In this work a new Lu^（3＋） PVC-membrane sensor based on 2,2＇-dithiobis（4-methylthiazole）（TMT） has been fabricated.The sensor exhibits a Nernstian slope of 19.6±0.4 mV decade（？） in the concentration range of 1.0×10~6-1.0×10~2 mol L^1 and a detection limit of 6.8×10~7 mol L^1.It could work well in the pH range of 2.7-9.6.The selectivity of the sensor against a lot of common alkaline,alkaline earth,transition,heavy metals and specially lanthanide ions was very good.展开更多
N^1,N^2-Bis[1-（2-hydroxyphenyl）methylidene]ethanedihydrazide（MEH） was used as new compound which plays the role of an excellent ion carrier in the fabrication of a Ho（Ⅲ） membrane electrode.The electrode shows a...N^1,N^2-Bis[1-（2-hydroxyphenyl）methylidene]ethanedihydrazide（MEH） was used as new compound which plays the role of an excellent ion carrier in the fabrication of a Ho（Ⅲ） membrane electrode.The electrode shows a good selectivity for Ho（Ⅲ） ion with respect to most common cations including alkali,alkaline earth,transition and heavy metal ions.This electrode has a wide linear dynamic range from 1.0×10^（-6） to 1.0×10^（-2） mol/L with a Nernstian slope of 19.8±0.3 mV per decade and a low detection limit of 5.8×10^（-7） mol/L in the pH range of 2.5-9.8,while the response time was rapid（10 s）.The suggested sensor was applied to the determination of Ho（Ⅲ） ions in tap water and river water samples.展开更多
An investigation on the photophysical properties of the newly designed terbium imidazole-4,5-dicarboxylic acid complex encapsulated in the inert matrices (tetraethoxysilane, TEOS) was performed. The composite material...An investigation on the photophysical properties of the newly designed terbium imidazole-4,5-dicarboxylic acid complex encapsulated in the inert matrices (tetraethoxysilane, TEOS) was performed. The composite material was very stable and showed strong green emission in pure water. Interestingly, we discovered that the luminescence of hybrid material was selectively responsive to H2PO4-. 1H-NMR and fluorescence spectra supported that the receptor had strong affinity to dihydrogen phosphate. Meanwhile, the luminescence was quenched by Fe3+ when adding different metal ions such as Fe3+, Pd2+, Cd2+, Co2+ and Mn2+ concomitantly. Moreover, thin film was successfully pre-pared by the same materials and it also exhibited selective recognition behavior to the above two ions.展开更多
In this research,a new poly（vinyl chloride）（PVC） membrane sensor for Ho^3＋ ion based on N-phenyl-2-（thiophen-2- ylmethylene）hydrazinecarbothioamide（PHC） as an ionophore was prepared.This sensor demonstrated g...In this research,a new poly（vinyl chloride）（PVC） membrane sensor for Ho^3＋ ion based on N-phenyl-2-（thiophen-2- ylmethylene）hydrazinecarbothioamide（PHC） as an ionophore was prepared.This sensor demonstrated good selectivity and sensitivity towards the holmium ion in comparison with variety of cations,including alkali,alkaline earth,transition and heavy metal ions.The effect of membrane composition and pH on the response properties of the electrode was investigated.In detail,the suggested sensor exhibited a Nernstian behavior（with a slope of 20.4±0.3 mV decade^-1） in the range of 1.0×10^-6 to 1.0×10^-2 mol/L with a detection limit of 6.2×10^-7 mol/L.The response time was relatively quick in the whole concentration range（～5 s）.The sensor usage was found to be at least 10 weeks in a pH range of 3.3-10.9.It was successfully applied in determination of fluoride ions in mouth wash preparations.展开更多
文摘This paper presents the studying results of the sodium ion sensor device based on the SnO_2/ITO glass structure in the detection of rinsing solution for contact lenses.The selective membrane contains poly (vinyl chloride) (PVC),bis (2-ethylhexyl) sebacate (DOS),(12-crown-4) methylmalonate (B12C4),and sodium tetrakis (4-fluoropbenyl) borate dehydrate (NaTFBD). The final weight ratios are PVC:DOS:B12C4:NaTFBD=33:66:2:2.In this condition,the sensor has performances with linear sensitivity,short response time,good repeatability and selectivity.The sensor was used to measure the rinsing solution for the contact lenses.Because the experimental results show close to the accurate value for four commercial products,this sensor can preliminary be used in detecting the rinsing solution for the contact lenses.Using this structure and sodium-sensing membrane to construct the sodium sensor is proven successfully in this application.
文摘A cobalt-iron alloy thin-film electrode-based electrochemical hydrogen-phosphate-ion sensor was prepared by electrodepositing on an Au-coated Al2O3 substrate from an aqueous solution of metal-salts. The use of a cobalt-iron alloy electrode greatly improved the hydrogen-ion sensor response performance, i.e., the sensor worked stably for more than 7 weeks and showed a quick response time of several seconds. Among the cobalt and iron alloy systems tested, the electrodeposited Co58Fe42 thin-film electrode showed the best EMF response characteristics, i.e., the sensor exhibited a linear potentiometric response to hydrogen-phosphate ion at the concentration range between 1.0 × 10–5 and 1.0 × 10–2 M with the slope of –43 mV/decade at pH 5.0 and at 30℃. A sensing mechanism of the Co-based potentiometric hydrogen-phosphate ion sensor was proposed on the basis of results of instrumental analysis.
基金supported by the National Natural Science Foundation of China(22278010,22125801)the Science and Technology Innovation Key R&D Program of Chongqing(CSTB2024TIAD-STX0024)。
文摘Real-time monitoring of ion content variations in humans offers a noninvasive approach to ensuring health,made possible through wearable sensors.However,challenges such as the low capacitance of the solid-contact(SC)layer and the formation of a water layer hinder the low-concentration ion detection and stable performance of these sensors.To address these limitations,a novel design is proposed using graphene quantum dots(GQD)-doped polypyrrole(PPy)nano-dendritic membranes,combined with a hydrophobic Nafion membrane,for sweat ion sensors.The GQD-doped PPy membrane serves as the SC layer,where GQD enhance capacitance and the nano-dendritic structure improves ion-to-electron transduction efficiency.Meanwhile,the hydrophobic Nafion membrane prevents water layer formation,stabilizing the sensor's performance.This design significantly improves both the sensitivity(from 49 m V/decade to 70 m V/decade)and stability(potential drift decreasing from 1.3 m V/h to18.7μV/h)of the sensor.Leveraging this configuration,Na^(+)and K^(+)sensors are integrated onto a flexible electrode using a dispense-coupled inkjet printing technique.This enables real-time,continuous monitoring of Na^(+)and K^(+) concentrations in human sweat simultaneously.The proposed sensing device demonstrates strong potential for noninvasive sweat monitoring,contributing to enhanced health management in daily life.
文摘Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmium ions(Cd(Ⅱ)).In this study,we present a novel screen-printed carbon electrode(SPCE)modified with single crystallineα-Fe_(2)O_(3)nano-hexagons that functions as a sensor for detecting Cd(Ⅱ).The performance of the fabricated sensor was thoroughly assessed and compared with unmodified SPCE using the voltammetric method.The crystalline structure of the synthesizedα-Fe_(2)O_(3)nano-hexagons was confirmed through XRD,and surface analysis revealed an average diameter and thickness of 86 nm and 9 nm,respectively.Theα-Fe_(2)O_(3)modified SPCE yields a 7-fold enhanced response(at pH 5.0 vs.Ag/AgCl)to Cd(Ⅱ)than bare SPCE.The modified electrode effectively detects Cd(Ⅱ)with a linear response range of up to 333.0μmol/L and a detection limit of 0.65 nmol/L under ideal circumstances.This newly fabricated sensor offers significant potential for environmental monitoring applications by providing outstanding practicality,anti-interference ability,and repeatability for detecting Cd(Ⅱ)in water samples.
基金the National Research Foundation of Korea(NRF)Grant funded by the Ministry of Science and ICT(No.2021R1A2C1009926)“Basic project(referring to projects performed with the budget directly contributed by the Government to achieve the purposes of establishment of Government-funded research Institutes)”+3 种基金supported by the KOREA RESEARCH INSTITUTE of CHEMICAL TECHNOLOGY(KRICT)(SS2042-10)Basic research project(Project:21-3212-1)of the Korea institute of GeoscienceMineral resources funded by the Ministry of Science and ICT of Koreaby Nanomedical Devices Development Project of NNFC in 2021.
文摘Conductive inks based on graphene materials have received significant attention for the fabrication of a wide range of printed and flexible devices.However,the application of graphene fillers is limited by their restricted mass production and the low concentration of their suspensions.In this study,a highly concentrated and conductive ink based on defect-free graphene was developed by a scalable fluid dynamics process.A high shear exfoliation and mixing process enabled the production of graphene at a high concentration of 47.5 mg mL^(−1)for graphene ink.The screen-printed graphene conductor exhibits a high electrical conductivity of 1.49×10^(4)S m^(−1)and maintains high conductivity under mechanical bending,compressing,and fatigue tests.Based on the as-prepared graphene ink,a printed electrochemical sodium ion(Na^(+))sensor that shows high potentiometric sensing performance was fabricated.Further,by integrating a wireless electronic module,a prototype Na^(+)-sensing watch is demonstrated for the real-time monitoring of the sodium ion concentration in human sweat during the indoor exercise of a volunteer.The scalable and efficient procedure for the preparation of graphene ink presented in this work is very promising for the low-cost,reproducible,and large-scale printing of flexible and wearable electronic devices.
基金the Natural Science Foundation of Shaanxi Province，the Special Foundation of the Education Department of Shaanxi Province，the Special Research Fund of Xianyang Normal University for Talent Introduction
基金the National Key Research and Development Program of China (No.2018YFC1602905)the National Natural Science Foundation of China (Nos.61871180 and 61527806)+1 种基金the Natural Science Foundation of Hunan Province (No.2017JJ2069)Hunan Key Research Project (No.2017SK2174) for the financial supports
文摘An electrochemical sensor based on self-made nano-porous pseudo carbon paste electrode(nano-PPCPE)has been successfully developed,and used to detect Cd^2+ and Pb^2+.The experimental results showed that the electrochemical performance of nanoPPCPE is evidently better than both glassy carbon electrode(GCE)and pure carbon paste electrode(CPE).Then the prepared nano-PPCPE was applied to detect Cd^2+ and Pb^2+in standard solution,the results showed that the electrodes can quantitatively detect trace Cd^2+ and Pb^2+,which has great significance in electrochemical analysis and detection.The linear ranges between the target ions concentration and the D PASV current were from 0.1-3.0 μmol/L,0.05-4.0 μmol/L for Cd^2+ and Pb^2+,respectively.And the detection limits were 0.0780 μmol/L and 0.0292 μmol/L,respectively.Moreover,the preparation of the nano-PPCPE is cheap,simple and has important practical value.
基金the financial support of the National Natural Science Foundation of China (No. 21202083)Natural Science Foundation of Jiangsu (Nos. BK2011055, BK2011551)the China Postdoctoral Science Foundation (No. 2012M511717)
文摘A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of these pillar[5]arene-based pseudorotaxanes and polypseudorotaxanes occurred upon the addition of Cl,Br,and I（tetrabutylammonium salts）,respectively,leading to their fluorescence recovery.The fluorescence enhancement of the pseudorotaxane and the polypseudorotaxanes increases in the order of I
基金the financial support from the National Natural Science Foundation of China (Nos. 20345006 and 20575043)
文摘CdSe/CdS quantum dots （QDs） functionalized by thiourea （TU） were synthesized and used as a fluorescent sensor for mercury ion detection. The TU-functionalized QDs were prepared by bonding TU via electrostatic interaction to the core/shell CdSe/CdS QDs after capping with thioglycolic acid （TGA）. It was observed that the fluorescence of the functionalized QDs was quenched upon the addition of Hg^2＋. The quantitative detection of Hg^2＋ with this fluorescent sensor could be conducted based on the linear relationship between the extent of quenching and the concentration of Hg^2＋ added in the range of 1-300 μg.L^-1, A detection limit of 0.56 μg.L^-1 was achieved. The sensor showed superior selectivity for Hg^2＋ and was successfully applied to the determination of mercury in environmental samples with satisfactory results
基金financed by the Graduate Innovation Foundation of Logistic Engineering University(Chongqing, China)
文摘A novel and simple fluorescent molecular sensor,1-pyrenecarboxaldehyde thiosemicarbazone（Hpytsc）,was synthesized.Its higher sensitivity and selectivity to mercury（Ⅱ） ion were studied through absorption and emission channels.The UV-vis spectra show that the increasing mercury（Ⅱ） ion concentrations result in the decreasing absorption intensity.The fluorescence monomer emission of Hpytsc is enhanced upon binding mercury（Ⅱ） ion,which should be due to the 1：1 complex formation between Hpytsc and metal ion.
基金the kind financial support provided by the Research Council of Quchan Islamic Azad University
文摘In this study,a new Er^3＋ sensor based on N-（benzyloxycarbonyloxy）succinimide（BCS） as a neutral carrier has been constructed. The sensor exhibits potential linear response with a Nernstian slope of 20.5±0.4 mV/decade in the concentration range of 1.0×10^-6to 1.0×10^-2mol/L of Er^3＋.It has a very short response time（10 s）,detection limit of 6.3×10^-7 mol/L and a good selectivity relative to a wide variety of other metal ions including common alkali,alkaline earth,heavy,and transition metal ions.It can be used in the pH range of 2.5-10.6 without any considerable divergence in potentials.The proposed sensor was successfully applied for the recovery of Er^3＋ ions spiked in tap and river water samples.
基金supported by the National Natural Science Foundation of China(No.21302081)the Scientific Fund of Sichuan Province,China(No.2014JQ0052)
文摘A highly efficient coupling reaction of N-heterocyclic carbene precursors with sulfonyl azides has been developed, affording a variety of pyrido[1,2-c][1,2,4]triazole-based π-conjugated triazenes. The present reaction proceeds under very mild conditions with good functional group tolerance. The resulting triazenes exhibit selective and sensitive fluorescent response toward Fe3+ion.
文摘In order to examine the hydronium ion （proton）-releasing functions in cells, [pH]out （extracellular pH） was measured using an ion image sensor composed of a 2D （two-dimensional） array of potential sensitive pixels. Using gastric tissues prepared from the stomach, pH distribution was observed during the histamine stimulation. The 2D distribution of [pH]out in the gastric tissues showed clear differences between the mucosal sides and the serous side. Even before the histamine stimulation, the mucosal side of the gastric mucosa showed a slightly lower pH than that of serous side. In the mucosal side, [pH]out decreased after the onset of the stimulation. The ion image sensor was capable of visualizing [pH]out in the gastric tissues. The present chemical-sensing technique realized a label-free microscopic assessment of the 2D distributions of biologically interesting substances, and consequently, [pH] out imaging via chemical microscopy has a future potential in medical fields for endoscopic analysis of gastric ulcers.
基金supports from the National Science Foundations of China (Nos. 20875076 and 21005061)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20096101120011)+2 种基金the Natural Science Basic Research Plan in Shaanxi Province of China (No.2010JQ2013)the Education Department of Shaanxi Province,China (No. 09JK759)the NWU Graduate Innovation and Creativity Funds (No. 09YSY04)
文摘An electrochemical sensor incorporating a signal enhancement for the determination of lead （II） ions （Pb2＋） was designed on the basis of the thrombin-binding aptamer （TBA） as a molecular recog- nition element and ionic liquid supported cerium oxide （CeO2） nanoparticles-carbon nanotubes compo- site modification. The composite comprises nanoparticles CeO2, multi-waU carbon nanotubes （MWNTs） and hydrophobic room temperature ionic liquid （RTIL） 1-ethyl-3-methylimidazolium tetrafluoroborate （EMIMBF4）. The electrochemical sensors were fabricated by immersing the CeOa-MWNTs-EMIMBF4 modified glassy carbon electrode （GCE） into the solution of TBA probe. In the presence of Pb2＋, the TBA probe could form stable G-quartet structure by the specific binding interactions between Pb2＋ and TBA. The TBA-bound Pb2＋ can be electrochemically reduced, which provides a readout signal for quantitative detection of Pb2＋. The reduction peak current is linearly related to the concentration of Pb2＋ from 1.0 ＊ 10-8 M to 1.0 ＊ 105 M with a detection limit of 5 ＊ 109 M. This work demonstrates that the CeOz-MWNTs-EMIMBF4 nanocomposite modified GCE provides a promising platform for immobi- lizing the TBA probe and enhancing the sensitivity of the DNA-based sensors.
基金the Research Council of the Quchan Islamic Azad University for the financial support of this research
文摘In this work a new Lu^（3＋） PVC-membrane sensor based on 2,2＇-dithiobis（4-methylthiazole）（TMT） has been fabricated.The sensor exhibits a Nernstian slope of 19.6±0.4 mV decade（？） in the concentration range of 1.0×10~6-1.0×10~2 mol L^1 and a detection limit of 6.8×10~7 mol L^1.It could work well in the pH range of 2.7-9.6.The selectivity of the sensor against a lot of common alkaline,alkaline earth,transition,heavy metals and specially lanthanide ions was very good.
文摘N^1,N^2-Bis[1-（2-hydroxyphenyl）methylidene]ethanedihydrazide（MEH） was used as new compound which plays the role of an excellent ion carrier in the fabrication of a Ho（Ⅲ） membrane electrode.The electrode shows a good selectivity for Ho（Ⅲ） ion with respect to most common cations including alkali,alkaline earth,transition and heavy metal ions.This electrode has a wide linear dynamic range from 1.0×10^（-6） to 1.0×10^（-2） mol/L with a Nernstian slope of 19.8±0.3 mV per decade and a low detection limit of 5.8×10^（-7） mol/L in the pH range of 2.5-9.8,while the response time was rapid（10 s）.The suggested sensor was applied to the determination of Ho（Ⅲ） ions in tap water and river water samples.
基金Project supported by the National Natural Science Foundation of China (21002035)Start Funding of South China Normal University (G21117)
文摘An investigation on the photophysical properties of the newly designed terbium imidazole-4,5-dicarboxylic acid complex encapsulated in the inert matrices (tetraethoxysilane, TEOS) was performed. The composite material was very stable and showed strong green emission in pure water. Interestingly, we discovered that the luminescence of hybrid material was selectively responsive to H2PO4-. 1H-NMR and fluorescence spectra supported that the receptor had strong affinity to dihydrogen phosphate. Meanwhile, the luminescence was quenched by Fe3+ when adding different metal ions such as Fe3+, Pd2+, Cd2+, Co2+ and Mn2+ concomitantly. Moreover, thin film was successfully pre-pared by the same materials and it also exhibited selective recognition behavior to the above two ions.
文摘In this research,a new poly（vinyl chloride）（PVC） membrane sensor for Ho^3＋ ion based on N-phenyl-2-（thiophen-2- ylmethylene）hydrazinecarbothioamide（PHC） as an ionophore was prepared.This sensor demonstrated good selectivity and sensitivity towards the holmium ion in comparison with variety of cations,including alkali,alkaline earth,transition and heavy metal ions.The effect of membrane composition and pH on the response properties of the electrode was investigated.In detail,the suggested sensor exhibited a Nernstian behavior（with a slope of 20.4±0.3 mV decade^-1） in the range of 1.0×10^-6 to 1.0×10^-2 mol/L with a detection limit of 6.2×10^-7 mol/L.The response time was relatively quick in the whole concentration range（～5 s）.The sensor usage was found to be at least 10 weeks in a pH range of 3.3-10.9.It was successfully applied in determination of fluoride ions in mouth wash preparations.
