A new strategy using an arnperometric biosensor with Escherichia coli （E. coli） that provides a rapid toxicity determination of chemical compounds is described. The CellSense biosensor system comprises a biological ...A new strategy using an arnperometric biosensor with Escherichia coli （E. coli） that provides a rapid toxicity determination of chemical compounds is described. The CellSense biosensor system comprises a biological component immobilized in intimate contact with a transducer which converts the biochemical signal into a quantifiable electrical signal. Toxicity assessment of heavy metals using E.coli biosensors could be finished within 30 min and the 50% effective concentrations （ECso） values of four heavy metals were determined. The results shows that inhibitory effects of four heavy metals to E.coli can be ranked in a decreasing order of Hg^2＋ 〉 Cu^2＋ 〉 Zn^2＋ 〉 Ni^2＋, which accords to the results of conventional bacterial counting method. The toxicity test of organic compounds by using CellSense biosensor was also demonstrated. The CellSense biosensor with E. coli shows a good, reproducible behavior and can be used for reproducible measurements.展开更多
A conductometric nitrate biosensor based on methyl viologen/Nafion/nitrate reductase（NR） interdigitated electrode for heavy metal determination was proposed.The activity of NR（EC 1.6.6.2） from Asper gillusniger（A...A conductometric nitrate biosensor based on methyl viologen/Nafion/nitrate reductase（NR） interdigitated electrode for heavy metal determination was proposed.The activity of NR（EC 1.6.6.2） from Asper gillusniger（A.niger） was assayed as a function of metal concentration in the presence of Cu^2＋,Zn^2＋,Cd^2＋ and Pb^2＋.Parameters influencing the performance of the biosensor were optimized for the application of it in the inhibition determination of heavy metal ions.Detection limits for Cu^2＋,Zn^2＋,Cd^2＋ and Pb^2＋ were about 0.05,0.5,0.1 and 1.0 μmol/L,respectively.The results show that NR activity could not be regained after exposure to Cu^2＋,but could be partially recovered after exposure to Zn^2＋,Pb^2＋ and Cd^2＋.展开更多
Maize tassel-multiwalled carbon nanotube (MT-MWCNT) composite has been used as a matrix for physical adsorption of horseradish peroxidase (HRP) onto the surface of a glassy carbon electrode through electrostatic inter...Maize tassel-multiwalled carbon nanotube (MT-MWCNT) composite has been used as a matrix for physical adsorption of horseradish peroxidase (HRP) onto the surface of a glassy carbon electrode through electrostatic interactions. The HRP/MT-MWCNT biosensor was applied for the detection of Zn2+ in aqueous solution. The biosensor designed was able to determine Zn2+ in the range of 0.35 - 12 mg/L with a detection limit of 7.5 μg/L. The inhibition was found to be reversible and uncompetitive when data were modeled using the Dixon and Cornish-Bowden plots. The biosensor was found to have good repeatability, reproducibility and high selectivity. The developed biosensor can be used to detect other HRP inhibiting trace metal ions.展开更多
In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via ...In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via biosensor system . The results obtained in this study indicate that the affinity of immobilised Ni(Ⅱ) ion affinity ligand for these peptides appear to be related to the arrangement of the histidine residues in the peptides. This study first documents the application of biosensor technique for paptide screening.展开更多
基金supported by the National Natural Science Foundation of China(No.20707014)the Program for Young Excellent Talents of Tongji University.
文摘A new strategy using an arnperometric biosensor with Escherichia coli （E. coli） that provides a rapid toxicity determination of chemical compounds is described. The CellSense biosensor system comprises a biological component immobilized in intimate contact with a transducer which converts the biochemical signal into a quantifiable electrical signal. Toxicity assessment of heavy metals using E.coli biosensors could be finished within 30 min and the 50% effective concentrations （ECso） values of four heavy metals were determined. The results shows that inhibitory effects of four heavy metals to E.coli can be ranked in a decreasing order of Hg^2＋ 〉 Cu^2＋ 〉 Zn^2＋ 〉 Ni^2＋, which accords to the results of conventional bacterial counting method. The toxicity test of organic compounds by using CellSense biosensor was also demonstrated. The CellSense biosensor with E. coli shows a good, reproducible behavior and can be used for reproducible measurements.
基金Supported by the National Natural Science Foundation of China(No.20707014)the Opening Foundation of the Environmental Engineering Key Discipline,Zhejiang University of Technology,China(No.20080205)
文摘A conductometric nitrate biosensor based on methyl viologen/Nafion/nitrate reductase（NR） interdigitated electrode for heavy metal determination was proposed.The activity of NR（EC 1.6.6.2） from Asper gillusniger（A.niger） was assayed as a function of metal concentration in the presence of Cu^2＋,Zn^2＋,Cd^2＋ and Pb^2＋.Parameters influencing the performance of the biosensor were optimized for the application of it in the inhibition determination of heavy metal ions.Detection limits for Cu^2＋,Zn^2＋,Cd^2＋ and Pb^2＋ were about 0.05,0.5,0.1 and 1.0 μmol/L,respectively.The results show that NR activity could not be regained after exposure to Cu^2＋,but could be partially recovered after exposure to Zn^2＋,Pb^2＋ and Cd^2＋.
文摘Maize tassel-multiwalled carbon nanotube (MT-MWCNT) composite has been used as a matrix for physical adsorption of horseradish peroxidase (HRP) onto the surface of a glassy carbon electrode through electrostatic interactions. The HRP/MT-MWCNT biosensor was applied for the detection of Zn2+ in aqueous solution. The biosensor designed was able to determine Zn2+ in the range of 0.35 - 12 mg/L with a detection limit of 7.5 μg/L. The inhibition was found to be reversible and uncompetitive when data were modeled using the Dixon and Cornish-Bowden plots. The biosensor was found to have good repeatability, reproducibility and high selectivity. The developed biosensor can be used to detect other HRP inhibiting trace metal ions.
文摘In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via biosensor system . The results obtained in this study indicate that the affinity of immobilised Ni(Ⅱ) ion affinity ligand for these peptides appear to be related to the arrangement of the histidine residues in the peptides. This study first documents the application of biosensor technique for paptide screening.
