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Xiandeng Hou - One of the best experts on this subject based on the ideXlab platform.

  • Hydride Generation for Headspace Solid-Phase Extraction with CdTe Quantum Dots Immobilized on Paper for Sensitive Visual Detection of Selenium
    Analytical Chemistry, 2015
    Co-Authors: Ke Huang, Xiandeng Hou, Wei Zhu, Lu Yang, Chengbin Zheng
    Abstract:

    A low-cost, simple, and highly selective analytical method was developed for sensitive visual detection of selenium in human urine both outdoors and at home, by coupling Hydride Generation with headspace solid-phase extraction using quantum dots (QDs) immobilized on paper. The visible fluorescence from the CdTe QDs immobilized on paper was quenched by H2Se from Hydride Generation reaction and headspace solid-phase extraction. The potential mechanism was investigated by using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) as well as Density Functional Theory (DFT). Potential interferences from coexisting ions, particularly Ag+, Cu2+, and Zn2+, were eliminated. The selectivity was significantly increased because the selenium Hydride was effectively separated from sample matrices by Hydride Generation. Moreover, due to the high sampling efficiency of Hydride Generation and headspace solid phase extraction, the sensitivity and the limit of detection (LOD) were significantly improved compar...

  • Recent Advance of Hydride Generation–Analytical Atomic Spectrometry: Part I—Technique Development
    Applied Spectroscopy Reviews, 2012
    Co-Authors: Zhou Long, Yamin Luo, Chengbin Zheng, Pengchi Deng, Xiandeng Hou
    Abstract:

    Abstract Hydride Generation is the most popular and widely used chemical vapor Generation technique and is interesting to analytical chemists as an effective sample introduction method, especially for elemental determination and speciation analysis by analytical atomic spectrometry. The present review provides a literature survey on the Hydride Generation technique coupled to analytical atomic spectrometry during the past several years, covering the literature on both tetrahydroborate-based Hydride Generation and non-tetrahydroborate-based Hydride Generation techniques. Development of other related methods coupled to Hydride Generation for better analytical performance of analytical atomic spectrometry is included as well.

  • recent advance of Hydride Generation analytical atomic spectrometry part i technique development
    Applied Spectroscopy Reviews, 2012
    Co-Authors: Zhou Long, Yamin Luo, Chengbin Zheng, Pengchi Deng, Xiandeng Hou
    Abstract:

    Abstract Hydride Generation is the most popular and widely used chemical vapor Generation technique and is interesting to analytical chemists as an effective sample introduction method, especially for elemental determination and speciation analysis by analytical atomic spectrometry. The present review provides a literature survey on the Hydride Generation technique coupled to analytical atomic spectrometry during the past several years, covering the literature on both tetrahydroborate-based Hydride Generation and non-tetrahydroborate-based Hydride Generation techniques. Development of other related methods coupled to Hydride Generation for better analytical performance of analytical atomic spectrometry is included as well.

Chengbin Zheng - One of the best experts on this subject based on the ideXlab platform.

  • Hydride Generation for Headspace Solid-Phase Extraction with CdTe Quantum Dots Immobilized on Paper for Sensitive Visual Detection of Selenium
    Analytical Chemistry, 2015
    Co-Authors: Ke Huang, Xiandeng Hou, Wei Zhu, Lu Yang, Chengbin Zheng
    Abstract:

    A low-cost, simple, and highly selective analytical method was developed for sensitive visual detection of selenium in human urine both outdoors and at home, by coupling Hydride Generation with headspace solid-phase extraction using quantum dots (QDs) immobilized on paper. The visible fluorescence from the CdTe QDs immobilized on paper was quenched by H2Se from Hydride Generation reaction and headspace solid-phase extraction. The potential mechanism was investigated by using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) as well as Density Functional Theory (DFT). Potential interferences from coexisting ions, particularly Ag+, Cu2+, and Zn2+, were eliminated. The selectivity was significantly increased because the selenium Hydride was effectively separated from sample matrices by Hydride Generation. Moreover, due to the high sampling efficiency of Hydride Generation and headspace solid phase extraction, the sensitivity and the limit of detection (LOD) were significantly improved compar...

  • Recent Advance of Hydride Generation–Analytical Atomic Spectrometry: Part I—Technique Development
    Applied Spectroscopy Reviews, 2012
    Co-Authors: Zhou Long, Yamin Luo, Chengbin Zheng, Pengchi Deng, Xiandeng Hou
    Abstract:

    Abstract Hydride Generation is the most popular and widely used chemical vapor Generation technique and is interesting to analytical chemists as an effective sample introduction method, especially for elemental determination and speciation analysis by analytical atomic spectrometry. The present review provides a literature survey on the Hydride Generation technique coupled to analytical atomic spectrometry during the past several years, covering the literature on both tetrahydroborate-based Hydride Generation and non-tetrahydroborate-based Hydride Generation techniques. Development of other related methods coupled to Hydride Generation for better analytical performance of analytical atomic spectrometry is included as well.

  • recent advance of Hydride Generation analytical atomic spectrometry part i technique development
    Applied Spectroscopy Reviews, 2012
    Co-Authors: Zhou Long, Yamin Luo, Chengbin Zheng, Pengchi Deng, Xiandeng Hou
    Abstract:

    Abstract Hydride Generation is the most popular and widely used chemical vapor Generation technique and is interesting to analytical chemists as an effective sample introduction method, especially for elemental determination and speciation analysis by analytical atomic spectrometry. The present review provides a literature survey on the Hydride Generation technique coupled to analytical atomic spectrometry during the past several years, covering the literature on both tetrahydroborate-based Hydride Generation and non-tetrahydroborate-based Hydride Generation techniques. Development of other related methods coupled to Hydride Generation for better analytical performance of analytical atomic spectrometry is included as well.

C.l. Madec - One of the best experts on this subject based on the ideXlab platform.

  • Determination of major antimony species in seawater by continuous flow injection Hydride Generation atomic absorption spectrometry
    Analytica Chimica Acta, 2004
    Co-Authors: Jean Yves Cabon, C.l. Madec
    Abstract:

    The capabilities and limitations of the continuous flow injection Hydride Generation technique, coupled to atomic absorption spectrometry, for the speciation of major antimony species in seawater, were investigated. Two pre-concentration techniques were examined. After continuous flow injection Hydride Generation and collection onto a graphite tube coated with iridium, antimony was determined by graphite furnace atomic absorption spectrometry. The low detection limits obtained (∼5ngl-1 for Sb(III) and ∼10ngl-1 for Sb(V) for 2.5ml seawater samples) permitted the determination of Sb(III) and total antimony in seawater with the use of selective Hydride Generation and on-line UV photooxidation. The number of samples that can be analyzed is about 15 per hour for Sb(III) determinations and 10 per hour for total antimony determinations. The analysis of seawater samples showed that Sb(V) was the predominant species, even in the presence of important biological activity. © 2003 Elsevier B.V. All rights reserved.

P. Riyazuddin - One of the best experts on this subject based on the ideXlab platform.

  • chemical interferences in Hydride Generation atomic spectrometry
    Trends in Analytical Chemistry, 2010
    Co-Authors: Ramesh A Kumar, P. Riyazuddin
    Abstract:

    This article presents an overview of chemical interferences observed in the determination of arsenic, antimony, bismuth, germanium, selenium, tellurium and tin by Hydride-Generation (HG) atomic spectrometric techniques. HG coupled with atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry are widely used. Concomitant mutual Hydride-forming, transition elements and acids (e.g., HNO3 and HF) used for sample digestion are the sources of interferences. We discuss the mechanisms of liquid-phase and gas-phase interferences in the light of recent studies reporting on the HG mechanism. We also discuss various approaches used to eliminate or to minimize the interferences. We present typical analytical applications, covering biological, environmental, geological and metallurgical samples.

  • Mechanism of volatile Hydride formation and their atomization in Hydride Generation atomic absorption spectrometry.
    Analytical Sciences, 2005
    Co-Authors: A. Ramesh Kumar, P. Riyazuddin
    Abstract:

    The mechanism of volatile Hydride Generation (HG) and the formation of analyte atoms in the quartz cell atomizer used in the determination of Hydride-forming elements (As, Bi, Ge, Pb, Sb, Sn, Te etc.) by atomic absorptionspectrometry (AAS), have been critically reviewed. The nascent hydrogen mechanism failed to explain Hydride Generation under different experimental conditions when tetrahydroborate (THB), amineboreanes (AB) and cyanotrihydroborate (CBH) were used as reductants. Various experimental evidence suggested a non-nascent hydrogen mechanism, in which the transfer of hydrogen directly bonded to boron to an analyte takes place. In electrochemical Hydride Generation (EcHG), the reduction of the analyte species and subsequent hydrogenation was proposed. The mechanism of analyte atom formation in a quartz tube atomizer has been explained by the following hypotheses: thermal decomposition, oxidation by O 2 and collisions by hydrogen free radicals. The free-radical mechanism satisfactorily explains most of the analytical implications. The significant variation in the experimental conditions required to generate different analyte Hydrides makes it difficult to arrive at a generalized mechanism of Hydride formation.

Olivier F X Donard - One of the best experts on this subject based on the ideXlab platform.

  • interferences during mercury speciation determination by volatilization cryofocusing gas chromatography and atomic absorption spectroscopy comparative study between Hydride Generation and ethylation techniques
    Journal of Analytical Atomic Spectrometry, 1998
    Co-Authors: Alberto De Diego, Chunmao Tseng, Teodor Stoichev, David Amouroux, Olivier F X Donard
    Abstract:

    The interfering effects of sodium chloride and a mixture of metal ions on the speciation determination of mercury by derivatization (Hydride Generation or ethylation), preconcentration by cryotrapping, gas chromatographic separation and detection by quartz furnace atomic absorption spectroscopy were investigated. The potential of the masking agent EDTA to overcome the interference was also studied. The experiments were arranged according to a 2n+1 factorial experimental design, so the possibility of synergistic effects among the variables considered was also taken into account. NaCl interferes in the determination of methylmercury (MeHg+) by ethylation, but causes fewer problems in the case of inorganic mercury (Hg2+) or if the analysis is carried out by Hydride Generation. The presence of metal ions strongly decreases the sensitivity in the determination of both compounds by Hydride Generation, but has no effect if ethylation is used as the derivatization technique. EDTA only partially eliminates the interfering effect of metals in the determination of MeHg+ by Hydride Generation. It also avoids decomposition of MeHg+ to Hg0 , promoted by NaCl, after derivatization of the compounds by Hydride Generation. The results obtained are discussed in terms of a comparison between the two derivatization techniques used, i.e., Hydride Generation and ethylation. Potential chemical pathways and reaction mechanisms for the observed interferences are also given.