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
Email: schalk@unf.edu
Website: @unf

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NIST 1577

Classification: Reference Material -> NIST -> 1577 -> Bovine liver

Citations 8

"Determination Of Selenium In Biological Samples Using ICP-QMS"
Atom. Spectrosc. 2000 Volume 21, Issue 5 Pages 149-155
Boulyga, S.;Dombovari, J.;Becker, J.S.;Dietze, H.J.

Abstract: A method for the determination of selenium traces in plant tissue samples is described. Freeze-dried and homogenized biological samples mere decomposed with HNO3, HF and H2O2 by using closed-vessel microwave digestion under temperature and pressure control. NIST SRM 1577b Bovine Liver and NIST SRM 1547 Peach Leaves reference materials were investigated to optimize the analytical procedure. Selenium concentrations were measured with quadrupole-based inductively coupled plasma mass spectrometry (ICP-QMS) using external calibration and the isotope dilution method. A special solution introduction device combining pneumatic nebulization with hydride generation in the thin liquid film on the walls of the minicyclonic spray chamber was employed for sample introduction into the ICP-MS, which allowed the sensitivity for Se to be increased by up to one order of magnitude without increasing the memory effects. SRMs were doped with different amounts (0, 0.1, 0.2, 0.5 and 1.0 µg/g) of enriched Se-78 spike (98.58% of Se-78) before digestion to study the method performance and selenium losses during sample preparation. For a given matrix selenium losses were reproducible as follows: 9.9±1.6% for Bovine Liver SRM, 15.8±3.6% for Peach Leaves SRM and 20.0±4.5% for the real plant tissue samples. The detection limit for selenium calculated for solid plant tissue was 0.2 µg/g (3s -criteria, m/z=82, digestion 1:1000) using conventional pneumatic nebulization for solution introduction and 0.03 µg/g for a combination of pneumatic nebulization with hydride generation. Applying the method developed, a large number of plant tissue samples were analyzed to study selenium behavior and accumulation in the environment.
Selenium Mass spectrometry Reference material Volatile generation

"Online Microwave Digestion Of Slurry Samples With Direct Flame Atomic Absorption Spectrometric Elemental Detection"
Analyst 1992 Volume 117, Issue 2 Pages 117-120
Stephen J. Haswell and David Barclay

Abstract: A flow injection system is described (with diagram) for online microwave digestion of slurried samples and AAS detection. Sample slurries were prepared in 5% HNO3 and portions (1 ml) were injected into the system and passed through a PTFE coil (20 m x 0.8 mm i.d.) in a microwave oven operated at 90% power (525 W). The digest was passed through a 5-m cooling loop in an antifreeze bath and then through a back-pressure regulator to the nebulizer of an AAS instrument. Recoveries of Mg, Ca, Zn and Fe from reference materials were 93.6 to 107%. Precision was 4 to 5%. A flow injection (FI) system for online microwave digestion of slurried samples with direct elemental determinations by flame atomic absorption spectrometry is described. Organic based elemental reference samples were prepared as slurries in 5% (by volume) HNO3 and the system was optimized for slurry mass, acid strength and tube and microwave cavity geometry. Bubble formation during digestion was controlled by post-digestion cooling and pressure regulation. Comparison of direct and FI calibrations indicated no apparent loss in sensitivity. Various samples (e.g. chlorella, mussel, sargasso, pepperbush, bovine liver reference materials) were examined and elemental recoveries for Ca, Fe, Mg, and Zn were typically found to be in the range 94-107% with precisions of less than 4.5% relative standard deviation. The major source of error was found to be in the dispersion of solids (<180 µm) as slurries in dilute HNO3. The throughput of samples in the system developed was 1-2 min per sample.
Magnesium Calcium Zinc Iron Sample preparation Spectrophotometry Microwave Online digestion Slurry Reference material

"Fullerene: A Sensitive And Selective Sorbent For The Continuous Preconcentration And Atomic Absorption Determination Of Cadmium"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 4 Pages 453-457
Yaneira Petit de Pe&ntilde;a, Mercedes Gallego, Miguel Val&aacute;crcel

Abstract: The use is described, with diagrams of the flow injection manifold used, of a column of 80 mg of fullerene C60 for the separation and pre-concentration of Cd as its pyrrolidine-1-carbodithioate complex. The sample solution (6 ml) of 3-300 ng of Cd2+ in 0.1 M HNO3 is injected into a stream (0.3 ml/min) of 0.1% ammonium pyrrolidine-1-carbodithioate solution in aqueous 5% ethanol, and the resulting complex is adsorbed on the fullerene, from which it is subsequently eluted with 0.2 mL of IBMK for online flame AAS. This combination of fullerene and chelating agent is superior to other continuous-flow separation/pre-concentration systems. Other heavy metals are tolerated in 600-1000-fold concentrations with respect to Cd; also, the results for Cd in standard reference oyster tissue, porcine kidney and bovine liver showed that there is negligible interference from the decomposition products of these samples.
Cadmium Sample preparation Spectrophotometry Sample preparation Preconcentration MIBK Reference material Interferences Extraction

"Simultaneous Determination Of Silicon And Phosphorus In Biological Standard Materials With Online-column Flow Injection Spectrophotometry"
Fresenius J. Anal. Chem. 1988 Volume 332, Issue 2 Pages 162-166
Yoshio Narusawa, Tsutomu Katsura and Fuki Kato

Abstract: Biological standard material (1 g), viz, NIES chlorella or pepperbush or NBS bovine liver, was ashed, the ash was fused with Li2CO3 - H3BO3 for 15 min at ~1000°C, and the cooled melt was dissolved in and diluted to 100 mL with 1 M HCl. A 2.5 mL portion of extract was diluted with water (2.5 ml) and the mixture was cleaned up by cation exchange on a column (3 cm x 8 mm) of Dowex 50W-X8 (100 to 200 mesh) pre-conditioned with 2 M HCl (10 ml) and water (2 x 10 ml). Elution was effected with 0.5 M HCl (5 x 2 ml), the combined eluates were evaporated to dryness, 0.5 mL of 0.25 M Na2CO3 was added and, after evaporation to dryness, the residue was fused at ~1000°C for 15 min. The melt was dissolved in water containing 0.01 M EDTA (1 ml) and the solution was diluted to 25 mL with water. Phosphorus and Si were then determined by flow injection analysis as previously described (Anal. Abstr., 1988, 50, 8B123) with online anion-exchange separation on a column (15 cm x 4.6 mm) of TSK-gel SAX (5 µm). Most commonly occuring ions, e.g., Ca and Mg, were removed on the cation-exchange column; however, arsenate and germanate were not. Results agreed with those by ICP-AES.
Silicon Phosphorus Ion exchange Spectrophotometry Merging zones Method comparison Simultaneous analysis Reference material

"Flame Atomic Absorption Spectrometric Determination Of Cadmium And Copper In Biological Reference Materials Using Online Sorbent Extraction Preconcentration"
Fresenius J. Anal. Chem. 1992 Volume 344, Issue 12 Pages 535-540
Shukun Xu, Michael Sperling and Bernhard Welz

Abstract: Animal or plant tissue reference material (0.5 g) was subjected to acid digestion and the residue was diluted with HNO3. Urine samples for analysis were diluted with water before addition of HNO3. The solution was loaded into a flow injection manifold where it was merged with a stream of 0.05% diethylammonium-NN-diethyldithiocarbamate. The complex formed was extracted online on a conical 100 µL micro-column of RP-C 18 sorbent and the chelates were eluted with methanol directly into the nebulizer - burner system of the spectrometer. Small air segments introduced before and after elution prevented the eluent from mixing with the sample solution and increased sensitivity. A sampling frequency of 85 h-1 was achieved, with a sample loading time of 30 s at a flow rate of 4.0 mL min-1. The enrichment factor for Cd and Cu was 20 and the detection limits were 0.15 and 0.2 µg L-1 for Cd and Cu, respectively. The coefficient of variation were 2.3% for 10 µL L-1 of Cd and 1.4% for 45 µg L-1 of Cu (n = 11). The procedure was suitable for the determination of Cu in biological materials and for Cd in urine. Low recoveries were obtained for Cd in samples containing high levels of Cu and/or Fe. Cadmium and copper at the µg/g to ng/g level in plant and animal tissue reference materials, and at the µg/L level in urine were determined by flame atomic absorption spectrometry using online sorbent extraction pre-concentration based on flow injection techniques. Bonded silica reversed phase sorbent with octadecyl functional groups (RP-C 18), packed in a 100 µL column, was used to collect the diethylammonium-N,N-diethyldithiocarbamate (DDTC) complex formed online in the sample digests at low pH. Methanol was used to elute the analyte chelates directly into the nebulizer-burner system of the spectrometer. Small air segments introduced before and after elution prevented the eluent from mixing with the sample solution and increased the sensitivity. A sampling frequency of 85/h could be obtained with a sample loading time of 30 s at a flow rate of 4.0 mL/min. The enrichment factor for both elements was 20 and the enhancement factors, including the effect of the organic solvent and with the flow spoiler removed, were 126 and 114 for cadmium and copper, respectively. The detection limits (3s) were 0.15 µg/L for cadmium and 0.2 µg/L for copper. The precision was 2.3% and 1.4% RSD for 10 µg/L Cd and 45 µg/L Cu, respectively. (n = 11). Results for the determination of cadmium and copper in various biological reference materials were typically in good agreement with certified values. Low recoveries were observed, however, for cadmium in samples containing high levels of copper and/or iron, such as bovine liver.
Cadmium Copper Sample preparation Spectrophotometry Sample preparation Reference material Air segmentation Preconcentration C18 Solid phase extraction

"Hydride-generation Flow Injection Using Graphite Furnace Detection - Emphasis On Determination Of Tin"
Spectrochim. Acta B 1992 Volume 47, Issue 5 Pages 701-709
Zhang Li, Susan McIntosh, Glen R. Carnrick and Walter Slavin*

Abstract: Hydride-forming analytes were separated from large volume of matrix by trapping the hydrides on a Pd-coated L'vov platform at low temperature before analysis by AAS. The Pd-treated stabilized-temp. platform furnace was used for in situ trapping and atomization of the analyte, and was at least 80% efficient for As, Bi, Ge, Sb, Se, Sn and Te. The method was tested by determining Sn in steel, river sediment, orchard leaves and bovine liver standard reference materials. The detection limit for Sn was 7 ng l-1, and the coefficient of variation was 31.5% at the 1.0 ng level. Other hydride-forming elements did not interfere.
Arsenic Bismuth Germanium Antimony Selenium Tellurium Tin Spectrophotometry Interferences Volatile generation Reference material Volatile generation

"Separation And Determination Of Copper And Zinc By Ion Chromatography Using 2-(2-benzoxazolylazo)-1-naphthol As A Post-column Derivatization Reagent"
Bunseki Kagaku 1998 Volume 47, Issue 11 Pages 861-866
Shin-ichiro Okawa, Kazuhiko Yamazaki and Tosimi Ishikawa

Abstract: An ion chromatography method using post-column derivatization with 2-(2-benzoxazolylazo)-1-naphthol(α-BOAN) in a nonionic surfactant solution of Brij35 was established for the separation and determination of Cu(II) and Zn(II). The optimum conditions for determining the elements were: an eluent containing 0.25 mol L-1 lactic acid (pH 3.1) at a flow rate of 1 mL min-1; for post-column derivatization, 2 x 10^-4 mol L-1 α-BOAN solution containing 4%(v/v) dioxane, 4%(w/v) Brij35 and sodium tetraborate at a flow rate of 0.3 mL min-1; pH at the drain of 3.3 ± 0.1; analytical column, a Shim-pack IC-C1 (5.0 mm i.d x 150 mm); oven temperature of 40°C; an injection volume of 0.02 mL; and detection at 565 nm. A linear relationship was observed between the peak hight and the amt. of elements within ranges of 80-240 and 400-2000 ppb for Cu and Zn, respectively. The relative standard deviations for the measurements (n = 7) of 120 ppb Cu and 800 ppb Zn were 2.2 and 2.0%, respectively. The detection limits of 16 ppb Cu and 195 ppb Zn (S/N = 3) were obtained. The present method was applied to the separation and determination of Cu(II) and Zn(II) in the Rice Flour (NIST SRM1568a) and Bovine Liver (NIST SRM1577b) with satisfactory results. Cu(II) and Zn(II) in rice from Australia, Thailand, China, and the U.S.A. are also determined by this method.
Copper Zinc HPIC Spectrophotometry Post-column derivatization Reference material Method comparison Optimization

"Determination Of Lead And Cadmium In Food Samples By Flow Injection Atomic Absorption Spectrometry"
Quim. Anal. 1987 Volume 6, Issue 1 Pages 52-59
Becerra, G.;Burguera, J.L.;Burguera, M.

Abstract: Samples are dried at 105°C, then wet-ashed with 30% H2O2 solution at 50°C and subsequently at 110°C after adding HNO3. The solution is evaporated and the residue is dissolved in 0.1 M HNO3 before analysis with a flow system as described by Fukamachi and Ishibashi (Anal. Chim. Acta, 1980, 119, 383) and air - acetylene flame AAS. Standards are analyzed similarly and peak heights are measured and averaged. Detection limits for a 10-g sample are 0.23 and 0.05 µg g-1 of Pb and Cd, respectively. Results obtained on NBS bovine liver and oyster tissue agreed well with the certified values.
Cadmium Lead Sample preparation Spectrophotometry Reference material