A PVC membrane enoxacin ion-selective electrode based on a needle-shaped inner reference electrode was prepared. A Ag/AgCl wire was used as the substrate of this electrode. It was previously coated with a thin sheet o...A PVC membrane enoxacin ion-selective electrode based on a needle-shaped inner reference electrode was prepared. A Ag/AgCl wire was used as the substrate of this electrode. It was previously coated with a thin sheet of urea-formaldehyde resin containing Cl - ions to form a needle-shaped inner reference electrode, then the inner reference electrode was coated with a thin sheet of a PVC membrane containing an enoxacin tetraphenylborate ion-pair complex. The influences of various ion-pair complexes, concentrations of the active components in the membrane and the plasticizers on the performance of the electrode were studied by orthogonal design. The linear response range of the electrode was 7.9×10 -5 -1.0×10 -2 mol/L. The detection limit was 2.0×10 -5 mol/L. The slope was 30.4 mV/decade(25 ℃). The electrode can be used for the potentiometric determination of enoxacin tablets directly. The average recovery was 100.4%, and the RSD was 0.9%. The results agreed with those determined by the method in Chinese Pharmacopoeia.展开更多
An ion-selective electrode(ISE)-based immunoassay has been innovatively designed for the sensitive detection of liver cancer biomarker(alpha-fetoprotein,AFP),using metal sulfide quantum dot(QD)-based nano labels.Cd S ...An ion-selective electrode(ISE)-based immunoassay has been innovatively designed for the sensitive detection of liver cancer biomarker(alpha-fetoprotein,AFP),using metal sulfide quantum dot(QD)-based nano labels.Cd S QDs-aggregated PAMAM dendrimer(QD-DE)was first synthesized and functionalized with polyclonal rabbit anti-human AFP antibodies.Thereafter,a sandwich immunoreaction was implemented on monoclonal mouse anti-human AFP antibody-coated microplate by using antibody-functionalized QD-DE as the secondary antibody.Accompanying the immunocomplex,subsequent potentiometric detection of cadmium ion dissolved from the QD-DE under acidic condition was conducted on a portable cadmium ion-selective electrode(Cd-ISE).Results revealed that the electrode potential of the Cd-ISE increased with the increment of AFP concentration from 0.1 to 100 ng m L^(-1)at a detection limit(LOD)of 68 pg m L^(-1).The relative standard deviations(RSD)were below9.09%and 10.54%for the intra-and inter-assay,respectively.Additionally,six human serum specimens were determined on CdISE-based immunosensor by using commercial human AFP ELISA kit as the reference,and gave good relationship between two methods.Importantly,Cd-ISE-based immunoassay offers the promise for simple and cost-effective screening of disease-related biomarkers.展开更多
A new all-solid-state carbonate ion-selective electrode was fabricated via electrochemical and ion-exchange reactions with Ag nanoparticles and Ag2CO3-BaCO3 as ion-to-electron transducer and ion-selective layer, respe...A new all-solid-state carbonate ion-selective electrode was fabricated via electrochemical and ion-exchange reactions with Ag nanoparticles and Ag2CO3-BaCO3 as ion-to-electron transducer and ion-selective layer, respectively. This paper presented the detailed procedures of the construction of the electrode, the applications of the electrode in various experiments, and the corresponding chemical reaction principles involved. The fabricated electrode was characterized by means of scanning electron microscopy（SEM）, energy dispersive spectrometer（EDS）, and electrochemical analyses. The electrode exhibited stable linear responses to carbonate anions（10-5--10-1 mol/L） with average Slope of the curve being -26.56 mV per decade, and showed negligible responses to NO3, SO2-, and Sal- anions. The electrode was further used to measure the concentration of carbonate anions in boiler water. The measured concentration was lower than that determined via titration. Overall, the electrode exhibited the advantages of miniaturized size, robust construction, and compatibility with other equipment and thus could be ideally integrated into various sensor platforms to collect chemical data from industrial heat exchangers.展开更多
In this work a PVC membrane electrode based on bis（N-3-methyl phenyl salicylidenaminato）copper（II）as ionophore was prepared.The electrode was tested by inorganic anions and showed good selectivity for thiocyanate ...In this work a PVC membrane electrode based on bis（N-3-methyl phenyl salicylidenaminato）copper（II）as ionophore was prepared.The electrode was tested by inorganic anions and showed good selectivity for thiocyanate ion.This sensor showed Nerstian behavior with a slope of a-59.3 mV per decade at 25℃.The proposed electrode exhibited a wide linear range from 1.0 × 10^-6 mol/L to 1.0× 10^-1 mol/L with a detection limit of 5.0×10^-7 mol/L.The electrode response was independent of pH in the range of 4.0-10.0.The response time is about 9-21s,and the electrode can be used for over 60 days without considerable deterioration.The prepared sensor was applied as an indicator electrode in potentiometric titration of SCN^- with Ag^＋ ion and to determine the thiocyanate in samples of urine and saliva.展开更多
文摘A PVC membrane enoxacin ion-selective electrode based on a needle-shaped inner reference electrode was prepared. A Ag/AgCl wire was used as the substrate of this electrode. It was previously coated with a thin sheet of urea-formaldehyde resin containing Cl - ions to form a needle-shaped inner reference electrode, then the inner reference electrode was coated with a thin sheet of a PVC membrane containing an enoxacin tetraphenylborate ion-pair complex. The influences of various ion-pair complexes, concentrations of the active components in the membrane and the plasticizers on the performance of the electrode were studied by orthogonal design. The linear response range of the electrode was 7.9×10 -5 -1.0×10 -2 mol/L. The detection limit was 2.0×10 -5 mol/L. The slope was 30.4 mV/decade(25 ℃). The electrode can be used for the potentiometric determination of enoxacin tablets directly. The average recovery was 100.4%, and the RSD was 0.9%. The results agreed with those determined by the method in Chinese Pharmacopoeia.
基金supported by the National Natural Science Foundation of China (21675029, 21665009, 21475025)the Key Joint Project for Health Education of Fujian Province (WKJ2016-2-15)the Program for Changjiang Scholars and Innovative Research Team in University (IRT15R11)
文摘An ion-selective electrode(ISE)-based immunoassay has been innovatively designed for the sensitive detection of liver cancer biomarker(alpha-fetoprotein,AFP),using metal sulfide quantum dot(QD)-based nano labels.Cd S QDs-aggregated PAMAM dendrimer(QD-DE)was first synthesized and functionalized with polyclonal rabbit anti-human AFP antibodies.Thereafter,a sandwich immunoreaction was implemented on monoclonal mouse anti-human AFP antibody-coated microplate by using antibody-functionalized QD-DE as the secondary antibody.Accompanying the immunocomplex,subsequent potentiometric detection of cadmium ion dissolved from the QD-DE under acidic condition was conducted on a portable cadmium ion-selective electrode(Cd-ISE).Results revealed that the electrode potential of the Cd-ISE increased with the increment of AFP concentration from 0.1 to 100 ng m L^(-1)at a detection limit(LOD)of 68 pg m L^(-1).The relative standard deviations(RSD)were below9.09%and 10.54%for the intra-and inter-assay,respectively.Additionally,six human serum specimens were determined on CdISE-based immunosensor by using commercial human AFP ELISA kit as the reference,and gave good relationship between two methods.Importantly,Cd-ISE-based immunoassay offers the promise for simple and cost-effective screening of disease-related biomarkers.
文摘A new all-solid-state carbonate ion-selective electrode was fabricated via electrochemical and ion-exchange reactions with Ag nanoparticles and Ag2CO3-BaCO3 as ion-to-electron transducer and ion-selective layer, respectively. This paper presented the detailed procedures of the construction of the electrode, the applications of the electrode in various experiments, and the corresponding chemical reaction principles involved. The fabricated electrode was characterized by means of scanning electron microscopy（SEM）, energy dispersive spectrometer（EDS）, and electrochemical analyses. The electrode exhibited stable linear responses to carbonate anions（10-5--10-1 mol/L） with average Slope of the curve being -26.56 mV per decade, and showed negligible responses to NO3, SO2-, and Sal- anions. The electrode was further used to measure the concentration of carbonate anions in boiler water. The measured concentration was lower than that determined via titration. Overall, the electrode exhibited the advantages of miniaturized size, robust construction, and compatibility with other equipment and thus could be ideally integrated into various sensor platforms to collect chemical data from industrial heat exchangers.
文摘In this work a PVC membrane electrode based on bis（N-3-methyl phenyl salicylidenaminato）copper（II）as ionophore was prepared.The electrode was tested by inorganic anions and showed good selectivity for thiocyanate ion.This sensor showed Nerstian behavior with a slope of a-59.3 mV per decade at 25℃.The proposed electrode exhibited a wide linear range from 1.0 × 10^-6 mol/L to 1.0× 10^-1 mol/L with a detection limit of 5.0×10^-7 mol/L.The electrode response was independent of pH in the range of 4.0-10.0.The response time is about 9-21s,and the electrode can be used for over 60 days without considerable deterioration.The prepared sensor was applied as an indicator electrode in potentiometric titration of SCN^- with Ag^＋ ion and to determine the thiocyanate in samples of urine and saliva.
