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 1568

Classification: Reference Material -> NIST -> 1568 -> Rice flour

Citations 3

"Hydride-generation Atomic Absorption Spectrometry Coupled With Flow Injection Analysis"
Anal. Chem. 1985 Volume 57, Issue 7 Pages 1382-1385
Manabu Yamamoto, Makoto Yasuda, and Yuroku Yamamoto

Abstract: Flow injection analysis was combined with the gas-segmentation method described by Skeggs (Am. J. Clin. Pathol., 1957, 28, 311) for the determination of As, Sb, Bi, Se and Te. On synthetic samples the coefficient of variation were between 0.5 and 0.8% (n = 10) with detection limits between 0.04 and 0.3 ng. The results on NBS steel, wheat and rice flour, orchard leaves and coal fly ash were close to certified values and the differential determination of As and Sb in thermal water was possible. Tolerance limits for diverse ions are listed.
Arsenic Antimony Bismuth Selenium Tellurium Spectrophotometry Reference material Segmented flow

"Determination Of Arsenic And Selenium By Hydride Generation Atomic Absorption Spectrometry Using A Gas-liquid Separator And A Dehydration Trap"
Microchem. J. 1996 Volume 53, Issue 1 Pages 18-25
Hisatake Narasaki and Jun-Yan Cao

Abstract: Biological material (0.25 g) was allowed to stand overnight in 3 mL concentrated HNO3, 0.5 mL concentrated H2SO4 and 1 mL 60% HClO4 were added and the mixture was digested under low heat until the fumes of HClO4 subsided. The digests, including siliceous residues, were transferred to a Pt dish with water and evaporated to 2 mL. The residues were dissolved with 5 mL 46% HF, 1 mL 9 M H2SO4 was added and the solution was concentrated to 2 mL. The pH was adjusted to 3.5 with 1 M NH3 and applied to a SPE column (35 cm x 10 mm i.d.) packed with 10 cm Chelex 100 chelating ion-exchange resin and the column was washed with 2 x 10 mL water. For the analysis of As; the column effluents were diluted to 100 mL with water and a 10 mL portion was mixed with 5 mL 6 M HCl. Portions of both acid solutions were introduced into the flow injection hydride generation system (schematic shown) and mixed with a stream of 2% sodium tetrahydroborate(III) solution in a Pyrex mixing coil (16 cm x 2 mm i.d.). The hydride generated was collected in a gas-liquid separator, dehydrated in a dehydration trap and swept into an electrically heated furnace with a carrier stream of N2 (2.5 l/min) by manipulating electromagnetic relays and timers (operating details given). The atomized As and Se species were detected at 193.7 and 196 nm, respectively, by AAS. The detection limits were 0.6 and 1 ng/ml, respectively. Tolerance levels to 10 foreign ions are listed. The method was applied to the analysis of five NIST Standard Reference materials (listed). Results agreed well with certified values.
Arsenic Selenium Spectrophotometry Reference material Chelex

"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