The Experts below are selected from a list of 35265 Experts worldwide ranked by ideXlab platform
Yonggang Zhao - One of the best experts on this subject based on the ideXlab platform.
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amine functional Magnetic Polymer modified graphene oxide as Magnetic solid phase extraction materials combined with liquid chromatography tandem mass spectrometry for chlorophenols analysis in environmental water
Journal of Chromatography A, 2014Co-Authors: Lixin Zhou, Yonggang Zhao, Xiaohong Chen, Haoyu ShenAbstract:Abstract A novel planar-structure amine-functional Magnetic Polymer modified graphene oxide nanocomposite (NH 2 -MP@GO) was synthesized. The properties were characterized by transmission electron microscopy (TEM) and Fourier-transform infrared spectrometry (FTIR). The obtained adsorption results showed that the NH 2 -MP@GO had great adsorptive ability toward five chlorophenols (CPs), including 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP). Based on these, an effective Magnetic solid-phase extraction (MSPE) procedure coupled with high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the preconcentration and determination of the five CPs in environmental water samples was developed. Various experimental parameters that could affect the extraction efficiencies had been investigated in detail. Under the optimum conditions, the enrichment factors of the method for the target CPs were found to be 1000. The proposed method was successfully applied for the analysis of environmental water samples with recoveries ranging from 86.4 to 99.8% with correlation coefficients ( R ) higher than 0.9994. Good linearities were obtained ranging from 10 to 500 ng/L for 2-CP, 5 to 500 ng/L for 2,4-DCP, 2 to 500 ng/L for 2,4,6-TeCP and 2,3,4,6-TeCP, and 1 to 500 ng/L for PCP, respectively. The limits of quantitation for the five CPs were 0.6–9.2 ng/L. It was confirmed that the planar-structure NH 2 -MP@GO was a kind of highly effective MSPE materials used for the trace CPs analyses.
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application of nanoring amino functionalized Magnetic Polymer dispersive micro solid phase extraction and ultra fast liquid chromatography tandem mass spectrometry in dicyandiamide residue analysis of powdered milk
Talanta, 2014Co-Authors: Xiaohong Chen, Yonggang Zhao, Shengdong Pan, Lixin Zhou, Micong JinAbstract:Abstract In this study, a rapid and accurate ultra-fast liquid chromatography–tandem quadrupole mass spectrometry (UFLC–MS/MS) method combined with dispersive micro-solid-phase extraction (d-µ-SPE) using a core–shell nanoring amino-functionalized Magnetic Polymer (CS-NR-MP) was established and validated to determine trace dicyandiamide (DCD) in powdered milk. The developed d-µ-SPE cleanup procedure can dramatically reduce the matrix in samples, and lead to a significant reduction in absolute matrix effects. Chromatographic separation was performed on an Acquity UPLC BEH Amide column by using water–acetonitrile (9:91, v/v) as the mobile phase within 2 min. DCD was quantitatively analyzed by using DCD-15N213C2 as an internal standard. The results showed that the recoveries were between 99.8 and 105.6% with RSDs in the range of 0.5–4.9%. The target compound had good linearity in the range of 0.1–20.0 µg L−1 with a correlation coefficient (r) of 0.9996. The limit of quantification (LOQ) was 0.06 µg kg−1. This method can be used for the rapid and sensitive determination of ultratrace DCD residue in powdered milk samples.
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preparation and characterization of amino functionalized nano fe3o4 Magnetic Polymer adsorbents for removal of chromium vi ions
Journal of Materials Science, 2010Co-Authors: Yonggang Zhao, Haoyu Shen, Shengdong Pan, Qinghua XiaAbstract:Four kinds of NH2-functionalized nano Magnetic Polymer adsorbents (NH2-NMPs) coupled with different diamino groups, i.e., ethylenediamine (EDA), diethylenetriamine (DETA), triethylentetramine (TETA), and tetraethylenepentamine (TEPA), named as EDA-NMPs, DETA-NMPs, TETA-NMPs, and TEPA-NMPs, respectively, have been prepared and characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), elementary analyzer (EA), Brunauer, Emmett, Teller surface area analyzer (BET), and Fourier transform infrared spectroscopy (FTIR). The sorptive characteristics of the NH2-NMPs intended for removal of chromium(VI) was investigated. Batch adsorption studies were carried out to optimize adsorption conditions. The evaluation of the adsorption kinetics, isotherm, and thermodynamics was deeply investigated. The results showed the adsorptive properties of the NH2-NMPs were highly pH dependent. Adsorption of Cr(VI) reached equilibrium within 30 min. The data of adsorption kinetics obeyed pseudo-second-order rate mechanism well. The adsorption data for Cr(VI) onto NH2-NMPs were well fitted to the Langmuir isotherm. The maximum adsorption capacities (q m) of the NH2-NMPs to Cr(VI) were 136.98, 149.25, 204.08, 370.37 mg g−1, for EDA-NMPs, DETA-NMPs, TETA-NMPs, and TEPA-NMPs, respectively. Thermodynamic parameters like ΔH θ, ΔS θ, and ΔG θ for the adsorption of Cr(VI) onto the NH2-NMPs have been estimated, which suggested that the adsorption processes of Cr(VI) onto the NH2-NMPs were endothermic and entropy favored in nature. The adsorption mechanism studies showed that the adsorption of Cr(VI) onto the NH2-NMPs could be related with electrostatic attraction, ion exchange, and coordination interactions.
Xiaohong Chen - One of the best experts on this subject based on the ideXlab platform.
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amine functional Magnetic Polymer modified graphene oxide as Magnetic solid phase extraction materials combined with liquid chromatography tandem mass spectrometry for chlorophenols analysis in environmental water
Journal of Chromatography A, 2014Co-Authors: Lixin Zhou, Yonggang Zhao, Xiaohong Chen, Haoyu ShenAbstract:Abstract A novel planar-structure amine-functional Magnetic Polymer modified graphene oxide nanocomposite (NH 2 -MP@GO) was synthesized. The properties were characterized by transmission electron microscopy (TEM) and Fourier-transform infrared spectrometry (FTIR). The obtained adsorption results showed that the NH 2 -MP@GO had great adsorptive ability toward five chlorophenols (CPs), including 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP). Based on these, an effective Magnetic solid-phase extraction (MSPE) procedure coupled with high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the preconcentration and determination of the five CPs in environmental water samples was developed. Various experimental parameters that could affect the extraction efficiencies had been investigated in detail. Under the optimum conditions, the enrichment factors of the method for the target CPs were found to be 1000. The proposed method was successfully applied for the analysis of environmental water samples with recoveries ranging from 86.4 to 99.8% with correlation coefficients ( R ) higher than 0.9994. Good linearities were obtained ranging from 10 to 500 ng/L for 2-CP, 5 to 500 ng/L for 2,4-DCP, 2 to 500 ng/L for 2,4,6-TeCP and 2,3,4,6-TeCP, and 1 to 500 ng/L for PCP, respectively. The limits of quantitation for the five CPs were 0.6–9.2 ng/L. It was confirmed that the planar-structure NH 2 -MP@GO was a kind of highly effective MSPE materials used for the trace CPs analyses.
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application of nanoring amino functionalized Magnetic Polymer dispersive micro solid phase extraction and ultra fast liquid chromatography tandem mass spectrometry in dicyandiamide residue analysis of powdered milk
Talanta, 2014Co-Authors: Xiaohong Chen, Yonggang Zhao, Shengdong Pan, Lixin Zhou, Micong JinAbstract:Abstract In this study, a rapid and accurate ultra-fast liquid chromatography–tandem quadrupole mass spectrometry (UFLC–MS/MS) method combined with dispersive micro-solid-phase extraction (d-µ-SPE) using a core–shell nanoring amino-functionalized Magnetic Polymer (CS-NR-MP) was established and validated to determine trace dicyandiamide (DCD) in powdered milk. The developed d-µ-SPE cleanup procedure can dramatically reduce the matrix in samples, and lead to a significant reduction in absolute matrix effects. Chromatographic separation was performed on an Acquity UPLC BEH Amide column by using water–acetonitrile (9:91, v/v) as the mobile phase within 2 min. DCD was quantitatively analyzed by using DCD-15N213C2 as an internal standard. The results showed that the recoveries were between 99.8 and 105.6% with RSDs in the range of 0.5–4.9%. The target compound had good linearity in the range of 0.1–20.0 µg L−1 with a correlation coefficient (r) of 0.9996. The limit of quantification (LOQ) was 0.06 µg kg−1. This method can be used for the rapid and sensitive determination of ultratrace DCD residue in powdered milk samples.
Lixin Zhou - One of the best experts on this subject based on the ideXlab platform.
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amine functional Magnetic Polymer modified graphene oxide as Magnetic solid phase extraction materials combined with liquid chromatography tandem mass spectrometry for chlorophenols analysis in environmental water
Journal of Chromatography A, 2014Co-Authors: Lixin Zhou, Yonggang Zhao, Xiaohong Chen, Haoyu ShenAbstract:Abstract A novel planar-structure amine-functional Magnetic Polymer modified graphene oxide nanocomposite (NH 2 -MP@GO) was synthesized. The properties were characterized by transmission electron microscopy (TEM) and Fourier-transform infrared spectrometry (FTIR). The obtained adsorption results showed that the NH 2 -MP@GO had great adsorptive ability toward five chlorophenols (CPs), including 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP). Based on these, an effective Magnetic solid-phase extraction (MSPE) procedure coupled with high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the preconcentration and determination of the five CPs in environmental water samples was developed. Various experimental parameters that could affect the extraction efficiencies had been investigated in detail. Under the optimum conditions, the enrichment factors of the method for the target CPs were found to be 1000. The proposed method was successfully applied for the analysis of environmental water samples with recoveries ranging from 86.4 to 99.8% with correlation coefficients ( R ) higher than 0.9994. Good linearities were obtained ranging from 10 to 500 ng/L for 2-CP, 5 to 500 ng/L for 2,4-DCP, 2 to 500 ng/L for 2,4,6-TeCP and 2,3,4,6-TeCP, and 1 to 500 ng/L for PCP, respectively. The limits of quantitation for the five CPs were 0.6–9.2 ng/L. It was confirmed that the planar-structure NH 2 -MP@GO was a kind of highly effective MSPE materials used for the trace CPs analyses.
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application of nanoring amino functionalized Magnetic Polymer dispersive micro solid phase extraction and ultra fast liquid chromatography tandem mass spectrometry in dicyandiamide residue analysis of powdered milk
Talanta, 2014Co-Authors: Xiaohong Chen, Yonggang Zhao, Shengdong Pan, Lixin Zhou, Micong JinAbstract:Abstract In this study, a rapid and accurate ultra-fast liquid chromatography–tandem quadrupole mass spectrometry (UFLC–MS/MS) method combined with dispersive micro-solid-phase extraction (d-µ-SPE) using a core–shell nanoring amino-functionalized Magnetic Polymer (CS-NR-MP) was established and validated to determine trace dicyandiamide (DCD) in powdered milk. The developed d-µ-SPE cleanup procedure can dramatically reduce the matrix in samples, and lead to a significant reduction in absolute matrix effects. Chromatographic separation was performed on an Acquity UPLC BEH Amide column by using water–acetonitrile (9:91, v/v) as the mobile phase within 2 min. DCD was quantitatively analyzed by using DCD-15N213C2 as an internal standard. The results showed that the recoveries were between 99.8 and 105.6% with RSDs in the range of 0.5–4.9%. The target compound had good linearity in the range of 0.1–20.0 µg L−1 with a correlation coefficient (r) of 0.9996. The limit of quantification (LOQ) was 0.06 µg kg−1. This method can be used for the rapid and sensitive determination of ultratrace DCD residue in powdered milk samples.
Haoyu Shen - One of the best experts on this subject based on the ideXlab platform.
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amine functional Magnetic Polymer modified graphene oxide as Magnetic solid phase extraction materials combined with liquid chromatography tandem mass spectrometry for chlorophenols analysis in environmental water
Journal of Chromatography A, 2014Co-Authors: Lixin Zhou, Yonggang Zhao, Xiaohong Chen, Haoyu ShenAbstract:Abstract A novel planar-structure amine-functional Magnetic Polymer modified graphene oxide nanocomposite (NH 2 -MP@GO) was synthesized. The properties were characterized by transmission electron microscopy (TEM) and Fourier-transform infrared spectrometry (FTIR). The obtained adsorption results showed that the NH 2 -MP@GO had great adsorptive ability toward five chlorophenols (CPs), including 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP). Based on these, an effective Magnetic solid-phase extraction (MSPE) procedure coupled with high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the preconcentration and determination of the five CPs in environmental water samples was developed. Various experimental parameters that could affect the extraction efficiencies had been investigated in detail. Under the optimum conditions, the enrichment factors of the method for the target CPs were found to be 1000. The proposed method was successfully applied for the analysis of environmental water samples with recoveries ranging from 86.4 to 99.8% with correlation coefficients ( R ) higher than 0.9994. Good linearities were obtained ranging from 10 to 500 ng/L for 2-CP, 5 to 500 ng/L for 2,4-DCP, 2 to 500 ng/L for 2,4,6-TeCP and 2,3,4,6-TeCP, and 1 to 500 ng/L for PCP, respectively. The limits of quantitation for the five CPs were 0.6–9.2 ng/L. It was confirmed that the planar-structure NH 2 -MP@GO was a kind of highly effective MSPE materials used for the trace CPs analyses.
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preparation and characterization of amino functionalized nano fe3o4 Magnetic Polymer adsorbents for removal of chromium vi ions
Journal of Materials Science, 2010Co-Authors: Yonggang Zhao, Haoyu Shen, Shengdong Pan, Qinghua XiaAbstract:Four kinds of NH2-functionalized nano Magnetic Polymer adsorbents (NH2-NMPs) coupled with different diamino groups, i.e., ethylenediamine (EDA), diethylenetriamine (DETA), triethylentetramine (TETA), and tetraethylenepentamine (TEPA), named as EDA-NMPs, DETA-NMPs, TETA-NMPs, and TEPA-NMPs, respectively, have been prepared and characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), elementary analyzer (EA), Brunauer, Emmett, Teller surface area analyzer (BET), and Fourier transform infrared spectroscopy (FTIR). The sorptive characteristics of the NH2-NMPs intended for removal of chromium(VI) was investigated. Batch adsorption studies were carried out to optimize adsorption conditions. The evaluation of the adsorption kinetics, isotherm, and thermodynamics was deeply investigated. The results showed the adsorptive properties of the NH2-NMPs were highly pH dependent. Adsorption of Cr(VI) reached equilibrium within 30 min. The data of adsorption kinetics obeyed pseudo-second-order rate mechanism well. The adsorption data for Cr(VI) onto NH2-NMPs were well fitted to the Langmuir isotherm. The maximum adsorption capacities (q m) of the NH2-NMPs to Cr(VI) were 136.98, 149.25, 204.08, 370.37 mg g−1, for EDA-NMPs, DETA-NMPs, TETA-NMPs, and TEPA-NMPs, respectively. Thermodynamic parameters like ΔH θ, ΔS θ, and ΔG θ for the adsorption of Cr(VI) onto the NH2-NMPs have been estimated, which suggested that the adsorption processes of Cr(VI) onto the NH2-NMPs were endothermic and entropy favored in nature. The adsorption mechanism studies showed that the adsorption of Cr(VI) onto the NH2-NMPs could be related with electrostatic attraction, ion exchange, and coordination interactions.
Micong Jin - One of the best experts on this subject based on the ideXlab platform.
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application of nanoring amino functionalized Magnetic Polymer dispersive micro solid phase extraction and ultra fast liquid chromatography tandem mass spectrometry in dicyandiamide residue analysis of powdered milk
Talanta, 2014Co-Authors: Xiaohong Chen, Yonggang Zhao, Shengdong Pan, Lixin Zhou, Micong JinAbstract:Abstract In this study, a rapid and accurate ultra-fast liquid chromatography–tandem quadrupole mass spectrometry (UFLC–MS/MS) method combined with dispersive micro-solid-phase extraction (d-µ-SPE) using a core–shell nanoring amino-functionalized Magnetic Polymer (CS-NR-MP) was established and validated to determine trace dicyandiamide (DCD) in powdered milk. The developed d-µ-SPE cleanup procedure can dramatically reduce the matrix in samples, and lead to a significant reduction in absolute matrix effects. Chromatographic separation was performed on an Acquity UPLC BEH Amide column by using water–acetonitrile (9:91, v/v) as the mobile phase within 2 min. DCD was quantitatively analyzed by using DCD-15N213C2 as an internal standard. The results showed that the recoveries were between 99.8 and 105.6% with RSDs in the range of 0.5–4.9%. The target compound had good linearity in the range of 0.1–20.0 µg L−1 with a correlation coefficient (r) of 0.9996. The limit of quantification (LOQ) was 0.06 µg kg−1. This method can be used for the rapid and sensitive determination of ultratrace DCD residue in powdered milk samples.