Entity

Time filter

Source Type


Hsiao P.-K.,National Sun Yat - sen University | Jiang S.-J.,National Sun Yat - sen University | Sahayam A.C.,National Center for Compositional Characterisation of Materials
Journal of Analytical Atomic Spectrometry | Year: 2011

The determination of B, Al, P, Fe, Ni, Cu, Zn, Cd and Pb in silicon powder by ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS) using citric acid as the modifier was investigated. The influences of instrument operating conditions and slurry preparation on the ion signals were studied. A relatively low vaporization temperature of 1900 °C was used, which separated the analyte from the major matrix components that not only improved ion signals significantly but also alleviated the spectral interferences caused by 28Si 29Si+, 28Si16O16O +, 28Si17O18O+ and 38Ar28Si+ on 57Fe+, 60Ni+, 63Cu+ and 66Zn+ determinations. The method has been applied to determine B, Al, P, Fe, Ni, Cu, Zn, Cd and Pb in a 99.999% pure silicon powder sample and four solar grade silicon powder samples using standard addition calibration methods. The concentrations that are in μg g-1 to sub μg g-1 levels were in good agreement with those of digested samples analyzed by pneumatic nebulization membrane desolvation ICP-MS. The precision between sample replicates was better than 9% with USS-ETV-ICP-MS technique. The method detection limit estimated from standard addition curves was about 8, 7, 9, 50, 9, 3, 7, 1 and 0.4 ng g-1 for B, Al, P, Fe, Ni, Cu, Zn, Cd and Pb, respectively, in original silicon samples. © 2011 The Royal Society of Chemistry. Source


Yang F.-Y.,National Sun Yat - sen University | Jiang S.-J.,National Sun Yat - sen University | Jiang S.-J.,Kaohsiung Medical University | Sahayam A.C.,National Center for Compositional Characterisation of Materials
Food Chemistry | Year: 2014

Speciation analysis of cobalt in nutritive supplements has been carried out using HPLC and ICP-MS equipped with a membrane desolvation sample introduction system as detector. In this study, cobalt containing compounds, namely Co(II), cyanocobalamin (CN-Cbl) and hydroxylcobalamin (OH-Cbl), were well separated by reversed phase HPLC with a C8-HPLC column as the stationary phase and 8 mmol L-1 ammonium acetate in 22% v/v methanol solution (pH 4) as the mobile phase using isocratic elution. Detection limit was in the range of 0.008-0.014 μg Co L-1 for various Co species. Over 98% of the total cobalt species was extracted in nutritive supplements using a 0.5% v/v HNO3 solution in a microwave field; and the spike recovery was in the range of 92-108% for various species. The HPLC-ICP-MS results showed a satisfactory agreement with the total cobalt concentrations obtained by ICP-MS analysis of completely dissolved samples. © 2013 Elsevier Inc. All rights reserved. Source


Hsu W.-H.,National Sun Yat - sen University | Jiang S.-J.,National Sun Yat - sen University | Jiang S.-J.,Kaohsiung Medical University | Sahayam A.C.,National Center for Compositional Characterisation of Materials
Talanta | Year: 2013

The determination of Cu, As, Hg and Pb in vegetable oils by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) was investigated. The oils were injected in the form of emulsions containing 5% m/v vegetable oil, 1.5% v/v Triton X-100 and 50 μg mL-1 ascorbic acid. Palladium nanoparticles (Pd-NPs) were used as modifier. The interference of 40Ar35Cl+ at arsenic mass m/z 75 was reduced significantly using dynamic reaction cell (DRC). Standard addition and isotope dilution methods were used for the quantifications. The method reported has been applied to the determination of Cu, As, Hg and Pb in selected vegetable oil samples purchased from a local market. The analytical results obtained were in good agreement with those of digested samples analyzed by pneumatic nebulization ICP-MS with 95% confidence according to Student t-test (except for Cu). Precision between sample replicates was better than 10% with the ETV-ICP-MS method. The detection limits obtained from standard addition curves were 0.4, 0.5, 1.1 and 0.4 ng g-1 for Cu, As, Hg and Pb, respectively, in the original oil samples. © 2013 Elsevier B.V. Source


Liao P.-H.,National Sun Yat - sen University | Jiang S.-J.,National Sun Yat - sen University | Jiang S.-J.,Kaohsiung Medical University | Sahayam A.C.,National Center for Compositional Characterisation of Materials
Journal of Analytical Atomic Spectrometry | Year: 2012

A simple and efficient cloud point extraction (CPE) procedure has been described for the preconcentration and separation of trace levels of Cd, Sb and Hg simultaneously from water samples for their determination by flow injection vapor generation inductively coupled plasma mass spectrometry (FI-VG-ICP-MS). The method was based on the formation of hydrophobic complexes of Cd, Sb and Hg with ammonium pyrrolidine dithiocarbamate (APDC), followed by their extraction, into a small volume of surfactant-rich phase, using a non-ionic surfactant Triton X-114. The main parameters affecting the extraction process such as concentration of complexing agent and pH, and also the amount of Triton X-114 were optimized. The surfactant-rich phase was dissolved with the carrier solution and then injected into VG-ICP-MS for Cd, Sb and Hg determination. The parameters affecting the vapor generation efficiency were also studied meticulously. Isotope dilution (ID) method was used for quantification work. The limit of detection for Cd, Sb and Hg was 0.002, 0.0006 and 0.005 ng mL -1, respectively. The accuracy of the procedure was verified by analyzing certified reference materials such as NRCC SLRS-4 River Water and NRCC SLEW-2 Estuarine Water reference materials, and also by applying it to a bottled mineral water, reservoir water and tap water samples obtained locally. © 2012 The Royal Society of Chemistry. Source


Yi Y.-Z.,National Sun Yat - sen University | Jiang S.-J.,National Sun Yat - sen University | Sahayam A.C.,National Center for Compositional Characterisation of Materials
Journal of Analytical Atomic Spectrometry | Year: 2012

Palladium nanoparticles (Pd-NPs) were used as the modifier for the determination of Zn, As, Cd, Sb, Hg and Pb in biological samples by ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS). The preparation and characterization of palladium nanoparticles (Pd-NPs) is described. Compared to traditional Pd aqueous solution, better ion signals were obtained when Pd-NPs was used as modifier. The influences of instrument operating conditions and slurry preparation on the ion signals were reported. The introduction of dry aerosol with ETV sampling device alleviated the spectral interferences effectively. This method has been applied for the determination of Zn, As, Cd, Sb, Hg and Pb in NIST SRM 1568a Rice Flour and SRM 1573a Tomato Leaves reference materials and two biological samples obtained locally. The analysis results of the reference material agree with the certified values. The results for the real world samples were also found to be in good agreement with the pneumatic nebulization ICP-MS results of the sample solutions. The method detection limits estimated from standard addition curves are in the range 1.9-3.6, 0.2-0.4, 0.5-0.8, 0.1-0.2, 0.4-0.8 and 0.4-0.6 ng g -1 for Zn, As, Cd, Sb, Hg and Pb, respectively, in original samples. © 2012 The Royal Society of Chemistry. Source

Discover hidden collaborations