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 -> NRCC -> DORM-1 -> Dogfish muscle

Citations 4

"Multisyringe Flow Injection System For Total Inorganic Arsenic Determination By Hydride Generation-atomic Fluorescence Spectrometry"
Anal. Chim. Acta 2002 Volume 455, Issue 2 Pages 277-285
N. V. Semenova, L. O. Leal, R. Forteza and V. Cerdà

Abstract: A software-controlled time-based multisyringe flow injection system for total inorganic arsenic determination by hydride generation atomic fluorescence spectrometry (HGAFS) has been developed. By using a multisyringe burette coupled with one multiport selection valve, the time-based injection provides precise known volumes of sample, a reducing sodium tetrahydroborate solution and a pre-reducing solution which are dispensed into a gas-liquid separation cell. An argon flow delivers the arsine into the flame of an atomic fluorescence spectrometer. A hydrogen flow has been used to support the flame. Linear calibration graphs for arsenic concentrations between 0.25 and 12 µg L-1 were obtained. The detection limit of the proposed technique (3s(b)/S) was 0.07 µg L-1. A sample throughput of 36 samples/h (108 injections) has been achieved. The proposed technique has been validated by means of reference solid and water materials with good agreement with the certified values. This method was compared with those reported in previous sequential injection analysis (SIA) and flow injection analysis (FIA) systems. The proposed method offers a number of advantages in front the usual AFS applications, which are mainly a higher sampling frequency and a significant reduction in reagent consumption.
Selenium, inorganic Fluorescence Multisyringe Method comparison Interferences Optimization Phase separator

"Determination Of Organomercury In Biological Reference Materials By Inductively Coupled Plasma Mass Spectrometry Using Flow Injection Analysis"
Anal. Chem. 1988 Volume 60, Issue 23 Pages 2587-2590
Diane Beauchemin, K. W. M. Siu, and S. S. Berman

Abstract: Samples of DORM-1 dogfish muscle and TORT-1 lobster hepatopancreas were acidified with HCl and extracted with toluene, and the organomercury compounds were back-extracted into aqueous cysteine acetate solution. Extracts were analyzed by isotope-dilution ICP-MS with use of a flow injection technique and a 100 µL sample loop in order to overcome interference caused by the presence of 4% of Na in the extracts. Results were compared with those obtained by GC - ECD. Methylmercury is the only significant organomercury compound present in DORM-1.
Ethylmercury Methylmercury ion Phenylmercury Clinical analysis Mass spectrometry Mass spectrometry Method comparison Reference material Interferences Speciation

"Comparison Of Sample Digestion Procedures For The Determination Of Arsenic In Certified Marine Samples Using The FI-HG-AAS-technique"
Fresenius J. Anal. Chem. 1997 Volume 357, Issue 7 Pages 817-821
G. Damkröger, M. Grote, E. Janßen

Abstract: For dry ashing, 0.2 g CRM (cod and mussel) were homogenized with 3 g MgO and 40 mL 0.75 M magnesium nitrate, evaporated at 130°C for ~3 h to near-dryness and ashed at 550°C overnight. The ash was dissolved by the dropwise addition of 25 mL 32% HCl and the solutions were diluted to 100 mL with water. For high-pressure ashing, 0.2 g mussel CRM and 0.16 g cod CRM were each mixed with 2 mL 65% HNO3 and 4 mL 30% H2O2 and then ashed with temperature programming from 50-70°C in 30 min, to 120°C in 30 min, then to 300°C (held for 80 min) in 15 min. The resulting clear solutions were diluted to 20 mL with water. For microwave digestion, 0.25 g mussel CRM and 0.2 g cod CRM were each mixed with 3 mL 65% HNO3, and 2 mL 30% H2O2 and irradiated at 250 W for 1 min, left to stand for 1 min, then irradiated at 250 W for 1.5 min, 450 W for 3 min, 850 W for 5 min and 250 W for 1 min. The resulting solutions were diluted to 25 mL with water. The solutions were analyzed for As by flow injection hydride-generation AAS (details given). Mean recoveries of As from mussel and cod were 13% and 2%, respectively, by microwave digestion and 56% and 25%, respectively, by high-pressure ashing. The dry ashing method gave quantitative recoveries from both CRM. Nitrite interference was overcome by the addition of an amino sulfuric acid (350 mM).
Arsenic Sample preparation Sample preparation Sample preparation Spectrophotometry Interferences Method comparison Reference material

"Preconcentration And Determination Of Inorganic Arsenic Using A Multisyringe Flow Injection System And Hydride Generation-atomic Fluorescence Spectrometry"
Talanta 2004 Volume 64, Issue 5 Pages 1335-1342
L. O. Leal, N. V. Semenova, R. Forteza and V. Cerdà

Abstract: A new multisyringe flow injection system for inorganic arsenic determination at trace levels by hydride generation-atomic fluorescence spectrometry (HGAFS) is presented. Preconcentration on a solid-phase was carried out using a column packed with an anion-exchange resin (Amberlite IRA-410). The reagents are dispensed to the system using a multisyringe burette coupled with two multi-port selection valves. Different parameters were changing in order to make the system as effective as possible. An analytical curve was obtained for arsenic determination between 50 and 2000 ng l-1. This new approach improved five times the sensitivity over a MSFIA-HGAFS technique developed previously by the authors. Detection limit of the proposed technique was (3sb/S) of 30 ng l-1. The relative standard deviation (RSD) of As at 1 µg L-1 was 4.8% (n=7). A sample throughput of 10 h-1 has been achieved. The proposed method has been applied to different reference solid and water materials with satisfactory results.
Arsenic, inorganic Fluorescence Preconcentration Solid phase extraction Amberlite Multisyringe Sensitivity Optimization