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 -> DOLT-1 -> Dogfish liver

Citations 2

"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

"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