The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Huangxian Ju - One of the best experts on this subject based on the ideXlab platform.
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electrochemical sensor for Lead Cation sensitized with a dna functionalized porphyrinic metal organic framework
Analytical Chemistry, 2015Co-Authors: Jie Wu, Jie Li, Huangxian JuAbstract:An efficient electrochemical sensor was presented for Lead Cation detection using a DNA functionalized iron–porphyrinic metal–organic framework (GR–5/(Fe–P)n-MOF) as a probe. The newly designed probe showed both the recognition behavior of GR–5 to Pb2+ with high selectivity and the excellent mimic peroxidase performance of (Fe–P)n-MOF. In the presence of Pb2+, GR–5 could be specifically cleaved at the ribonucleotide (rA) site, which produced the short (Fe–P)n-MOF-linked oligonucleotide fragment to hybridize with hairpin DNA immobilized on the surface of screen-printed carbon electrode (SPCE). Because of the mimic peroxidase property of (Fe–P)n-MOF, enzymatically amplified electrochemical signal was obtained to offer the sensitive detection of Pb2+ ranging from 0.05 to 200 nM with a detection limit of 0.034 nM. In addition, benefiting from the Pb2+-dependent GR–5, the proposed assay could selectively detect Pb2+ in the presence of other metal ions. The SPCE based electrochemical sensor along with the GR–5/...
Lin Cui - One of the best experts on this subject based on the ideXlab platform.
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electrochemical sensor for Lead Cation sensitized with a dna functionalized porphyrinic metal organic framework
Analytical Chemistry, 2015Co-Authors: Lin CuiAbstract:An efficient electrochemical sensor was presented for Lead Cation detection using a DNA functionalized iron-porphyrinic metal-organic framework (GR-5/(Fe-P)n-MOF) as a probe. The newly designed probe showed both the recognition behavior of GR-5 to Pb(2+) with high selectivity and the excellent mimic peroxidase performance of (Fe-P)n-MOF. In the presence of Pb(2+), GR-5 could be specifically cleaved at the ribonucleotide (rA) site, which produced the short (Fe-P)n-MOF-linked oligonucleotide fragment to hybridize with hairpin DNA immobilized on the surface of screen-printed carbon electrode (SPCE). Because of the mimic peroxidase property of (Fe-P)n-MOF, enzymatically amplified electrochemical signal was obtained to offer the sensitive detection of Pb(2+) ranging from 0.05 to 200 nM with a detection limit of 0.034 nM. In addition, benefiting from the Pb(2+)-dependent GR-5, the proposed assay could selectively detect Pb(2+) in the presence of other metal ions. The SPCE based electrochemical sensor along with the GR-5/(Fe-P)n-MOF probe exhibited the advantages of low-cost, simple fabriCation, high sensitivity and selectivity, providing potential appliCation of on-site and real-time Pb(2+) detection in complex media.
Jie Wu - One of the best experts on this subject based on the ideXlab platform.
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electrochemical sensor for Lead Cation sensitized with a dna functionalized porphyrinic metal organic framework
Analytical Chemistry, 2015Co-Authors: Jie Wu, Jie Li, Huangxian JuAbstract:An efficient electrochemical sensor was presented for Lead Cation detection using a DNA functionalized iron–porphyrinic metal–organic framework (GR–5/(Fe–P)n-MOF) as a probe. The newly designed probe showed both the recognition behavior of GR–5 to Pb2+ with high selectivity and the excellent mimic peroxidase performance of (Fe–P)n-MOF. In the presence of Pb2+, GR–5 could be specifically cleaved at the ribonucleotide (rA) site, which produced the short (Fe–P)n-MOF-linked oligonucleotide fragment to hybridize with hairpin DNA immobilized on the surface of screen-printed carbon electrode (SPCE). Because of the mimic peroxidase property of (Fe–P)n-MOF, enzymatically amplified electrochemical signal was obtained to offer the sensitive detection of Pb2+ ranging from 0.05 to 200 nM with a detection limit of 0.034 nM. In addition, benefiting from the Pb2+-dependent GR–5, the proposed assay could selectively detect Pb2+ in the presence of other metal ions. The SPCE based electrochemical sensor along with the GR–5/...
Jie Li - One of the best experts on this subject based on the ideXlab platform.
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electrochemical sensor for Lead Cation sensitized with a dna functionalized porphyrinic metal organic framework
Analytical Chemistry, 2015Co-Authors: Jie Wu, Jie Li, Huangxian JuAbstract:An efficient electrochemical sensor was presented for Lead Cation detection using a DNA functionalized iron–porphyrinic metal–organic framework (GR–5/(Fe–P)n-MOF) as a probe. The newly designed probe showed both the recognition behavior of GR–5 to Pb2+ with high selectivity and the excellent mimic peroxidase performance of (Fe–P)n-MOF. In the presence of Pb2+, GR–5 could be specifically cleaved at the ribonucleotide (rA) site, which produced the short (Fe–P)n-MOF-linked oligonucleotide fragment to hybridize with hairpin DNA immobilized on the surface of screen-printed carbon electrode (SPCE). Because of the mimic peroxidase property of (Fe–P)n-MOF, enzymatically amplified electrochemical signal was obtained to offer the sensitive detection of Pb2+ ranging from 0.05 to 200 nM with a detection limit of 0.034 nM. In addition, benefiting from the Pb2+-dependent GR–5, the proposed assay could selectively detect Pb2+ in the presence of other metal ions. The SPCE based electrochemical sensor along with the GR–5/...
K S Knight - One of the best experts on this subject based on the ideXlab platform.
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does altaite exhibit emphanitic behavior a high resolution neutron powder diffraction investigation of the crystallographic and thermoelastic properties of pbte between 10 and 500 k
Canadian Mineralogist, 2016Co-Authors: K S KnightAbstract:Abstract The recent claim, based on an analysis of the pair distribution function (pdf), that altaite, PbTe, exhibits emphanitic behavior above room temperature has been re-investigated using high resolution, neutron time-of-flight powder diffraction between 10 and 500 K. The results of this study refute the two supporting assertions of emphanisis, namely that the temperature dependence of the unit-cell parameter and the atomic displacement parameter of the Lead Cation in altaite behave in a non-Debye-like manner. Within the temperature interval 10 to 500 K, the thermoelastic properties of altaite can be treated in a simple, self-consistent phenomenological model in which the Cation and anion vibrate independently of one another in a Debye-like manner, with fitted vibrational Debye temperatures of 99.6(2) K for the Lead Cation and 156.0(5) K for the tellurium anion. Simultaneous fitting of the unit-cell volume and isochoric heat capacity in a self-consistent, two-term Debye internal energy model yields characteristic temperatures of 91(3) and 175(5) K, in good agreement with those values determined from fitting the atomic-displacement parameters. Taking into account the limitations of the Debye model for lattice vibrations, the calculated vibrational density of states derived from the two-term Debye model is found to be in fair agreement with that calculated by density functional theory. Both vibrational Debye temperatures closely match the mean predicted frequency cut-offs calculated from the partial phonon densities of states for the two constituent atomic species. The differences in conclusions drawn from this current investigation and the earlier pdf measurements are attributable to a linear temperature-dependent offset (decrease) from the published temperatures in the total scattering study. The offset is found to become significant around room temperature, with a magnitude that increases with increasing temperature. The supporting evidence for emphanitic behavior in altaite in the pdf study, such as discontinuities in the thermal expansion coefficient and the temperature variation of the atomic displacement parameters, are therefore most probably artefacts that arise from the sample temperature being substantially cooler than the claimed set-point temperature for temperatures greater that ∼300 K.
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a high resolution neutron powder diffraction investigation of galena pbs between 10 k and 350 k no evidence for anomalies in the lattice parameters or atomic displacement parameters in galena or altaite pbte at temperatures corresponding to the satur
Journal of Physics: Condensed Matter, 2014Co-Authors: K S KnightAbstract:The temperature dependences of the unit cell parameter and the atomic displacement parameters (adp) for galena (PbS) have been measured using high resolution neutron powder diffraction in the temperature interval 10–350 K. No evidence has been found for the anomalous behaviour recently reported in a total scattering study of galena, in which the temperature variation of both the unit cell and the adp for Lead are reported to undergo a dramatic reduction at a temperature of ~250 K. The linear thermal expansion coefficient calculated from the powder diffraction study is found to be in excellent agreement with literature values over the entire temperature interval studied, and approximately 25% greater at room temperature than that determined by analysis of the pair distribution function (pdf) derived from the total scattering data. This discrepancy is shown to be attributable to a linear, temperature-dependent offset from the published temperatures in the total scattering study, and has arisen from the sample temperature being significantly lower than the experimental set point temperature. Applying this correction to the adps of the Lead Cation removes the anomalous temperature dependence and shows the pdf results are in agreement with the neutron powder diffraction results. AppliCation of the identical temperature offsets to the results of the pdf analysis of data collected on altaite (PbTe) eliminates the anomalous behaviour in the unit cell and the adp for Lead, bringing them in line with literature values. Contrary to the conclusions of the pdf analysis, adps for the Lead Cation in both galena and altaite can be described in terms of Debye-like behaviour and are consistent with the partial phonon density of states.