University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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NIST 1643

Citations 12

"Development Of The Continuously Variable Volume Reactor For Flow Injection Analysis Part 1. Design, Capabilities And Testing"
Anal. Chim. Acta 2002 Volume 455, Issue 2 Pages 287-304
Linda L. Lipe, Suzanne M. Purinton, Elizabeth Mederios, C. Chad Harrell, Cynthia Efta, Melissa Murray, Meredith Wood, Ray-Bernard Portier and Stuart J. Chalk

Abstract: A new apparatus for mixing sample and reagent in flow injection analysis (FIA) is described. The continuously variable volume reactor (CVVR) replaces the conventional mixing coil in a flow injection (FI) manifold to provide mixing and dilution. A linear actuator motor allows control of the chamber volume via LabVIEW software. The chamber volume can be incremented in steps of I µL over the range 68-1704 µL. In addition, the chamber has an integral variable-speed stirring unit that is also under computer control. Experiments were performed to evaluate the dispersion characteristics of this new device, evaluate the volume reproducibility, and understand the mixing characteristics. Use of the chamber is shown in the determination of iron(II) in pond water, and in NIST SRM 1643d with excellent results and a detection limit of 3.7 µg/l iron(II). Advantages of the CVVR and future research activities using the device are discussed.
Iron(2+) Spectrophotometry Mixing chamber Automation Dilution Dispersion Gradient technique

"Coupled Techniques Based On Liquid Chromatography And Atomic Fluorescence Detection For Arsenic Speciation"
Anal. Chim. Acta 2000 Volume 411, Issue 1-2 Pages 71-79
Marc Vilanó, Antoni Padró and Roser Rubio

Abstract: Arsenic speciation is performed by using coupled techniques with anion and cation exchange columns and atomic fluorescence detection, with UV irradiation and hydride generation as derivatization steps. The coupling design is described. A new software is developed which provides a dynamic range wide enough to allow the quantification of arsenic species at very different concentration levels each in the same sample. Two chromatographic columns were used in separate analyzes, which permits the quantification of six arsenic compounds (arsenate, arsenate, monomethylarsonate (MMA), dimethylarsinate (DMA), arsenocholine (AsChol), arsenobetaine (AsBet)). Instrumental performance is optimized. Detection limits lower than 4 µg L-1 and precision lower than 5% RSD are achieved for all the compounds under study.
Arsenate ion Arsenite monomethylarsonic acid Dimethylarsinic acid Arsenocholine Arsenoβine HPLC Fluorescence Speciation UV reactor Reference material

"Fluorimetric Determination Of Dissolved Aluminum In Natural Waters After Liquid-liquid Extraction Into N-hexanol"
Anal. Chim. Acta 2000 Volume 405, Issue 1-2 Pages 31-42
J. Zhang, H. Xu and J. L. Ren

Abstract: A sensitive and selective extraction-fluorimetric method for the determination of trace amount of dissolved aluminum in natural waters is developed in this study. Aluminum-lumogallion complex (Al-LMG) is extracted into n-hexanol, and the fluorescence can be enhanced substantially up to 20-fold. Compared to other publications in the literature, the method reported here is free from matrix effects, and the interference from iron and fluoride has been minimised successfully by Be2+ and o-phenanthroline, respectively. The detection Limit of dissolved Al is 0.25 nM, which is one order of magnitude lower than the traditional fluorescence techniques, with a precision of 5% at an Al level of 40 nM and 6.7% at an Al level of 1.0 nM in routine analyzes. The inter-calibration with electro-thermal atomic absorption spectrometry (ETAAS) technique for a variety of natural water samples shows a difference of 5-10%. The analysis of international SRM 1643C reference material by the method developed here provides a result consistent with the certified value. The successful inter-laboratory calibration practice demonstrates again the merit of present analytical procedure for the determination of Al in environmental and marine sciences.
Aluminum, soluble Fluorescence Interferences Method comparison

"Improvement On Simultaneous Determination Of Chromium Species In Aqueous-solution By Ion Chromatography And Chemiluminescence Detection"
Anal. Chim. Acta 1997 Volume 354, Issue 1-3 Pages 107-113
Bente Gammelgaarda,*, Yi-ping Liaob and Ole Jønsa

Abstract: A sensitive method for the simultaneous determination of chromium(III) and chromium(VI) was chromatography and chemiluminescence detection. Two Dionex ion-exchange guard columns in series, CG5 and AG7, were used to separate chromium(III) from chromium(VI). Chromium(VI) was reduced by potassium sulfite, whereupon both species were detected by use of the luminol-hydrogen peroxide chemiluminescence system. Parameters affecting retention times and resolution of the separator columns, such as eluent pH, eluent composition, reductant pH and concentration, and flow rates were optimized. Furthermore, the stabilities of reductant and luminol solutions were studied. The linear range of the calibration curve for chromium(III) and chromium(VI) was 1-400 µg L-1. The detection limit was 0.12 µg L-1 for chromium(III) and 0.09 µg L-1 for chromium(VI), respectively. The precision at the 20 µg L-1 level was 1.4% for chromium(III) and 2.5% for chromium(VI), respectively. The accuracy of the chromium(III) determination was determined by analysis of the NIST standard reference material 1643 c, Trace elements in water with the result 19.1±1.0 µg Cr(III) L-1 (certified value 19.0±0.6 µg Cr(III) l-1). The method was applied to analyze the stability of chromium patches for contact dermatitis testing. 19 References
Chromium(III) Chromium(VI) Chemiluminescence HPIC Detection limit Optimization Post-column derivatization Precision Preconcentration Speciation Reference material

"Lead Hydride Generation For Isotope Analysis By Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1988 Volume 3, Issue 6 Pages 821-827
Xiaoru Wang, Miklos Viczian, Alexandra Lasztity and Ramon M. Barnes

Abstract: The hydride generator, which included a Thompson U-shaped glass phase separator or a porous PTFE tube separator, was coupled to a Sciex Elan 250 ICP-MS instrument. Generation and transfer of hydrides were optimized by flow injection ICP-MS; the best signal-to-noise ratio (SNR) was obtained with 0.6% HCl, 5% of NaBH4 in 0.1% NaOH solution and 1% of H2O2 (used for oxidation of Pb before hydride generation), and the optimum Ar flow rate was 1.46 l min-1. For standard solution containing 10 µg L-1 of Pb, calibration graphs were obtained by the isotope-dilution technique for 204Pb, 206Pb, 207Pb and 208Pb; the detection limits for each isotope were between 0.04 and 0.06 µg l-1. The technique was applied in the determination of Pb in NBS SRM 1643 (trace elements in water); recovery was quantitative and the coefficient of variation was 1.2% (n = 3). Ion abundances were also determined in certified galena and Pb samples (prep. described). The PTFE phase separator gave greater SNR and less interference. Interference from Fe(III) and Cu(II) was serious, but could be overcome by addition of sulfosalicylic acid and NaCN to the NaBH4 solution. The hydride-generation technique had significantly greater sensitivity for Pb than that involving nebulization.
Lead-206 Lead-204 Lead-207 Lead-208 Spectrophotometry Mass spectrometry Interferences Phase separator Reference material Teflon membrane Volatile generation Volatile generation

"Online Solid-phase Chelation For The Determination Of Eight Metals In Environmental Waters By Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 3 Pages 187-191
Daniel B. Taylor, H. M. Kingston, Donald J. Nogay, Dagmar Koller and Robert Hutton

Abstract: Seawater was mixed with 4 M ammonium acetate buffer, the pH was adjusted to 5.5 and diluted with water. The prepared seawater or natural water was loaded into a flow injection system at 2.4 ml/min and the sample merged with a buffer solution (2 ml/min) of 4 M ammonium acetate of pH 5.8 which had passed through a clean up Al-clad PEEK column (7.5 cm x 4.6 mm i.d.) packed with Muromac A-1 (50-100 mesh). The resulting solution was loaded on to a PEEK column (5 cm x 4 mm i.d.) and the column was washed with water. Weakly retained matrix components were eluted with buffer and the buffer was washed off the column with water. The metal analyzes were eluted with 1 M HNO3 and the eluate passed to the ICP-MS instrument via a V groove nebulizer. Eight metals (14 isotopes) were determined with detection limits of 0.5-60 ng/l for a 10 mL sample to 0.11-12 ng/l for a 50 mL sample (results tabulated). The results for the analysis of water reference materials are tabulated and discussed.
Metals Mass spectrometry Sample preparation Reference material Chelation Solid phase extraction Muromac

"Multi-element Analysis Using Flow Injection Inductively Coupled Plasma Mass Spectrometry: Analytical Aspects Of Multi-element Determinations In Highly Concentrated Solutions Of Phosphoric Acid, Sodium Phosphate And Sodium Nitrate"
Spectrochim. Acta B 1994 Volume 49, Issue 2 Pages 171-184
Huub Klinkenberg, Ton Beeren and Werner Van Borm

Abstract: Trace element concentrations of 51 elements in a matrix solution comprising 15% H3PO4, 16% NaNO3 and 6% Na3PO4 were determined by flow injection ICP-MS using an addition calibration method. A modified Perkin-Elmer Sciex Elan 500 instrument and an Eppendorf EVA flow injection system were used. The method did not have any of the disadvantages usually encountered with the continuous aspiration of very concentrated solution. Detection limits were of the order of 1-2 ng/ml.
Trace elements Mass spectrometry Multielement Interferences

"Simultaneous Determination Of Hydride And Non-hydride Forming Elements By Inductively Coupled Plasma Atomic-emission Spectrometry"
Anal. Proc. 1992 Volume 29, Issue 10 Pages 438-439
Zhang Li, Susan McIntosh and Walter Slavin

Abstract: Arsenic, Se, Sb, Bi, Cd, Cr, Cu, Fe, Mn, Ni and Pb were determined in the NIST environmental standard reference materials steel, coal fly ash, urban particulated and 1643b water by ICP-AES. A Perkin-Elmer FIAS-2000 flow injection system was used for hydride generation (experimental conditions tabulated). The sample solution was split into two streams, one being pumped directly to the nebulizer, the other mixed with HCl and NaBH4 solution in the mixing tubes of the chemifold. After separation, the hydride was swept into the spray chamber through a slightly modified cross-flow nebulizer cap. The hydride was then carried into the plasma together with sample aerosol. Recoveries of 20 µg L-1 of As, Sb and Se and 50 µg L-1 of non-hydride forming elements in river- and seawater standards were >80%.
Arsenic Selenium Antimony Bismuth Cadmium Chromium Copper Iron Manganese Nickel Lead Spectrophotometry Spectrophotometry Reference material FIAS-200 Nebulizer Volatile generation Volatile generation

"Gas Chromatography With Element Selective Detection In Speciation Analysis. Status And Future Prospects"
Analusis 1994 Volume 22, Issue 2 Pages 37-48

Abstract: A review is presented which discusses species separation by GC on columns of DB-1, HP-1 or RSL-150) followed by element-selective detection. Optical (AAS, AES, AFS) and MS detection methods are compared. Sample preparation, automation and flow injection processing are described and some practical applications are given. (67 references).
Trace elements GC Mass spectrometry Spectrophotometry Spectrophotometry Spectrophotometry Speciation Review

"Catalytic Determination Of Trace Elements By Flow Injection Analysis"
J. Flow Injection Anal. 1994 Volume 11, Issue 1 Pages 7-23
Teshima, N.;Nakano, S.;Kawashima, T.

Abstract: A review is presented of the use of catalytic reactions in FIA methods for trace analysis. Catalytic reactions are easily controlled in FIA by fixing the flow rate of the solution and the length of the reaction coil. Diagrams of the flow manifolds for Mn and V determinations are also presented. (56 references).
Manganese Vanadium Trace elements Catalysis Review

"Pneumatic Nebulizer As A Dilution Chamber In A Flow Injection System For Multielement Analysis By ICP-MS"
Quim. Nova 1998 Volume 21, Issue 4 Pages 405-409
Gomes Neto, José Anchieta; Silva, José Bento B.; Rodrigues Neto, Renato; Curtius, Adilson José; Souza, Ivan G.

Abstract: An automatic dispenser based on a flow injection system used to introduce sample and anal. solution into an inductively coupled plasma mass spectrometer through a spray chamber is proposed. Anal. curves were constructed after the injection of 20 to 750 µL aliquots of a multielement standard solution (20.0 µg L-1 in Li, Be, Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, Se, Sr, Ag, Cd, Ba, Tl, Pb) and the acquisition of the integrated transient signals. The linear concentration. range could be extended to ~five decades. The performance of the system was checked by analyzing a NiST 1643d reference material. Accuracy could be improved by the proper selection of the injected volume Besides good precision (relative standard deviation <2%), the results obtained with the proposed procedure were closer to the certified values of the reference material than those obtained by direct aspiration or by injecting 125 µL of several anal. solutions and samples.
Lithium Beryllium Aluminum Vanadium Chromium Manganese Nickel Cobalt Copper Zinc Arsenic Selenium Strontium Silver Cadmium Barium Thallium Lead Mass spectrometry Dilution Nebulizer Reference material

"On-Line Preconcentration System By Coprecipitation With Lanthanum Hydroxide Using Packed-Bed Filter For The Determination Of Tellurium In Water By ICP-OES With USN"
Instrum. Sci. Technol. 2004 Volume 32, Issue 4 Pages 423-431
M. Kaplan, S. Cerutti, S. Moyano, R. A. Olsina, L. D. Martinez, J. A. G&aacute;squez

Abstract: A sensitive procedure for the determination of total tellurium traces in water samples is described, which combines an on-line analyte pre-concentration system coupled to inductively coupled plasma optical emission spectrometry (ICP-OES) associated with flow injection (FI) and ultrasonic nebulization (USN). Tellurium was pre-concentrated by co-precipitation at pH 9.1 with lanthanum hydroxide precipitate. The precipitate was quantitatively collected on a packed-bed filter with Amberlite XAD-4 resin and subsequently eluted with 5% (v/v) nitric acid. A total enhancement factor of 140-fold was obtained with respect to ICP-OES using pneumatic nebulization. The detection limit (3s) for the pre-concentration of 10 mL of aqueous solution (3s) was 0.15 µg L-1. The precision for 10 replicate determination at the 10 µg L-1 tellurium level was 2.6%, relative standard deviation (RSD), calculated with the peak heights obtained. The calibration graph using the pre-concentration system for tellurium was linear with a correlation coefficient of 0.9995 at levels near the detection limit up to at least 100 µg L-1. Satisfactory results were obtained for the analysis of tellurium in the standard reference material NIST 1643d 'Trace Elements in Water' and tap water.
Tellurium Spectrophotometry Coprecipitation Amberlite Preconcentration Reference material