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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Classification: Reference Material -> NIES -> 5 -> Human hair

Citations 3

"Simultaneous Flow Injection Determination Of Iron(II) And Total Iron By Micelle Enhanced Luminol Chemiluminescence"
Anal. Chim. Acta 1998 Volume 376, Issue 2 Pages 247-254
Kumiko Saitoh, Takashi Hasebe, Norio Teshima, Makoto Kurihara and Takuji Kawashima*

Abstract: A flow injection method is proposed for the determination of Fe(II) and for the simultaneous determination of Fe(II) and total Fe based on the catalytic effect of Fe(II) on the oxidation of luminol with H2O2 in an alkaline medium. The activating effect for the catalysis of Fe(II) was extremely exhibited in the presence of citric acid, while citric acid acted as a masking agent for Fe(III). Also, the sensitivity of the method was enhanced by adding tetradecyltrimethylammonium bromide (TTAB) as a cationic surfactant together with citric acid. The Fe(III) in sample solution can be determined by passing through the Ag reductor column introduced in the FIA system to reduce Fe(III) to Fe(II), which allows total Fe determination Calibration graphs for Fe(II) and total Fe were linear over the range 5 x 10^-9-1 x 10^-6 mol L-1 at a rate of 18 samples h-1 (36 peaks h-1). The relative standard deviations (n = 10) for 4 x 10^-8 mol L-1 Fe(II) and 1 x 10^-7 mol L-1 total Fe were 3.0% and 1.5%, respectively. The proposed method was successfully applied to the determination of Fe in human hair (NIES, number 5) and natural waters.
Iron(2+) Iron Chemiluminescence Indirect Speciation Catalysis Micelle Surfactant Sensitivity Reference material

"Continuous-flow Cold Vapor Procedure For Mercury Determination By Atomic Emission Using The Reverse-flow Injection Approach"
Spectrochim. Acta B 1994 Volume 49, Issue 8 Pages 787-795
João Carlos De Andrade* and Maria Izabel M. S. Bueno

Abstract: The sample solution is pumped at 4 ml/min and 40-50 µL of 2-3% SnCl2 solution in 1.5-4 M HCl is injected into it. After passage of the mixing zone through a reaction coil the Hg is swept from the solution in a stream of He (100 ml/min) to a PTFE membrane in a permeation cell, and the permeated He and Hg pass to a quartz tube containing 0.3 g of Au foil on which the Hg is concentrated. The Hg is released by resistive heating and determined at 253.7 nm in an 11 W He DC plasma. Diagrams of the apparatus are presented. The calibration graph is linear up to 50 ng/ml of Hg2+ and the detection limit is ~50 pg/ml. For 15 replicate injections into 50 ng/ml of Hg2+ the RSD was 1.6%. Only selenite, sulfide and iodide interfere seriously, but the interference from sulfide and iodide can be removed by preparing the sample solution in an oxidizing acid medium. The result for reference standard human hair ('NIES Certified Reference Material, Human Hair', National Institute for Environmental Studies, Japan Environment Agency, Tsukuba, Japan, 1985) was 4.2 ± 0.1 µg/g (cf. the certified value of 4.4 ± 0.4 µg/g).
Mercury Spectrophotometry Interferences Reference material Teflon membrane Reverse Volatile generation Volatile generation

"Use Of Inductively Coupled Mass Spectrometry For Trace-metal Analysis In Natural Systems"
Lab. Pract. 1988 Volume 37, Issue 1 Pages 61-63
Eaton, A.N.;Hutton, R.C.

Abstract: Standard reference materials, e.g., human serum, tomato leaves, pine needles and hair, were analyzed with use of a VG PlasmaQuad ICP-MS instrument operated with recommended parameters (cf. Hutton and Eaton, J. Anal. Atomic Spectrom., 1987, 2, 595). The results (tabulated) show the method to be accurate; detection limits are typically at the pg mL-1 level. Use of the instrument in the rapid multi-element semi-quantitative screening mode as well as in the conventionally calibrated mode is described. A rapid data-acquisition system (Transcan) is available that permits elementary screening even for transient signals, e.g., from flow injection sample introduction.
Metals, trace Mass spectrometry Multielement Reference material