Cyanide ion was studied as an effector of Jack bean urease(JBU) at 300 K in 30 mmol/LTris buffer,pH 7 by isothermal titration calorimetry(ITC).The simple novel model was used for CN^- + JBU interaction over the whole ...Cyanide ion was studied as an effector of Jack bean urease(JBU) at 300 K in 30 mmol/LTris buffer,pH 7 by isothermal titration calorimetry(ITC).The simple novel model was used for CN^- + JBU interaction over the whole range of CN^- concentrations.The binding parameters recovered from the simple novel model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a noncooperative inhibitor of JBU,and there is a set of 12 identical and independent binding sites for CN^- ions.The di...展开更多
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry （ITC）. The extended solvation model was used f...Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry （ITC）. The extended solvation model was used for CN^- ＋ JBU interaction over the whole range of CN^- concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor ofurease, and there is a set of 12 ± 0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 umol/L. The molar enthalpy of binding is AH= -13.60 kJ mol^-1.展开更多
A new method of determination of trace CNin water was proposed.A thin film of AgS was electrochemically deposited on both sides of a silver coated piezoelectric crystal.The AgS Ag films can react with CN selectively,w...A new method of determination of trace CNin water was proposed.A thin film of AgS was electrochemically deposited on both sides of a silver coated piezoelectric crystal.The AgS Ag films can react with CN selectively,which causes the frequency shifts of the piezoelectric crystal.The frequency shifts are proportional to the concentration of CN in the range of 106~10'g/L.XPS experiments indicated the sensing film was AgiS Ag.A coordination complex Ag-CNwas formed when AgiS Ag film contacted with solution containing CNion.A response mechanism was proposed based on the XPS data.展开更多
The present study highlights the potential application of zinc peroxide （ZnO2） nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO2 synthesis ha...The present study highlights the potential application of zinc peroxide （ZnO2） nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO2 synthesis has been granted in United States of America （US Patent number 8,715,612; May 2014）, South Africa, Bangladesh, and India. The ZnO2 nanomaterial was capped with polyvinylpyrrolidone （PVP） to control the particle size. The PVP capped ZnO2 nanomaterial （PVP-ZnO2） before and after adsorption of cyanide was characterized by scanning electron microscope, transmission electron microscope, X-ray diffractorneter, Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrom- etry. The remaining concentration of cyanide after adsorption by PVP-ZnO2 was determined using ion chromatograph. The adsorption of cyanide over PVP-ZnO2 was also studied as a function of pH, adsorbent dose, time and concentration of cyanide. The maximum removal of cyanide was observed in pH range 5.8-7.8 within 15 rain. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.展开更多
The development of sensors for selective detection of cyanide ion(CN^-) is an important mission to accomplish because of the versatility and toxicity of CN^-. In the present work, an "ensemble"-based colorim...The development of sensors for selective detection of cyanide ion(CN^-) is an important mission to accomplish because of the versatility and toxicity of CN^-. In the present work, an "ensemble"-based colorimetric and fluorescent sensor(L2-Zn^(2+)) for CN^-ion has been developed. The addition of cyanide ions removed Zn^(2+) from the ensemble(L2-Zn^(2+)) in aqueous medium, resulting in a color change of the solution from red to buff and a "turn-on" fluorescent response. Also, the sensitivity of both the fluorescenceand colorimetric-based assay is below the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. In addition, test strips, which served as convenient and efficient CN^- test kits, were fabricated based on the sensor.Notably, the selective detection of cyanide with L2-Zn^(2+) for practical application was also performed in sprouting potatoes.展开更多
文摘Cyanide ion was studied as an effector of Jack bean urease(JBU) at 300 K in 30 mmol/LTris buffer,pH 7 by isothermal titration calorimetry(ITC).The simple novel model was used for CN^- + JBU interaction over the whole range of CN^- concentrations.The binding parameters recovered from the simple novel model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a noncooperative inhibitor of JBU,and there is a set of 12 identical and independent binding sites for CN^- ions.The di...
文摘Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry （ITC）. The extended solvation model was used for CN^- ＋ JBU interaction over the whole range of CN^- concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor ofurease, and there is a set of 12 ± 0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 umol/L. The molar enthalpy of binding is AH= -13.60 kJ mol^-1.
文摘A new method of determination of trace CNin water was proposed.A thin film of AgS was electrochemically deposited on both sides of a silver coated piezoelectric crystal.The AgS Ag films can react with CN selectively,which causes the frequency shifts of the piezoelectric crystal.The frequency shifts are proportional to the concentration of CN in the range of 106~10'g/L.XPS experiments indicated the sensing film was AgiS Ag.A coordination complex Ag-CNwas formed when AgiS Ag film contacted with solution containing CNion.A response mechanism was proposed based on the XPS data.
基金U.G.C New Delhi for the financial support through JRF(No.116459)
文摘The present study highlights the potential application of zinc peroxide （ZnO2） nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO2 synthesis has been granted in United States of America （US Patent number 8,715,612; May 2014）, South Africa, Bangladesh, and India. The ZnO2 nanomaterial was capped with polyvinylpyrrolidone （PVP） to control the particle size. The PVP capped ZnO2 nanomaterial （PVP-ZnO2） before and after adsorption of cyanide was characterized by scanning electron microscope, transmission electron microscope, X-ray diffractorneter, Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrom- etry. The remaining concentration of cyanide after adsorption by PVP-ZnO2 was determined using ion chromatograph. The adsorption of cyanide over PVP-ZnO2 was also studied as a function of pH, adsorbent dose, time and concentration of cyanide. The maximum removal of cyanide was observed in pH range 5.8-7.8 within 15 rain. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.
基金supported by the National Natural Science Foundation of China(21662031,21661028,21574104,21262032)the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(IRT 15R56)
文摘The development of sensors for selective detection of cyanide ion(CN^-) is an important mission to accomplish because of the versatility and toxicity of CN^-. In the present work, an "ensemble"-based colorimetric and fluorescent sensor(L2-Zn^(2+)) for CN^-ion has been developed. The addition of cyanide ions removed Zn^(2+) from the ensemble(L2-Zn^(2+)) in aqueous medium, resulting in a color change of the solution from red to buff and a "turn-on" fluorescent response. Also, the sensitivity of both the fluorescenceand colorimetric-based assay is below the maximum allowable level of cyanide ions in drinking water set by the World Health Organization. In addition, test strips, which served as convenient and efficient CN^- test kits, were fabricated based on the sensor.Notably, the selective detection of cyanide with L2-Zn^(2+) for practical application was also performed in sprouting potatoes.
