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Abstract  

A combination of solid phase extraction, coprecipitation, and neutron activation techniques has been used to develop a speciation analysis method based on green chemistry for the major arsenic species in drinking water. Arsenate as As(V), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) are separated and preconcentrated by strongly anion and cation exchange columns in tandem while As(III) remains in the effluent. These species are then selectively eluted and As(III) coprecipitated with bismuth sulphide. This simple method has been applied to the analysis of water reference materials with good results. The detection limits are 0.9, 1.7, 1.6, 3.8 and 16 ng mL−1 for As(III), As(V), MMA, DMA and total arsenic, respectively, using a neutron flux of 2.5 × 1011 cm−2 s−1 at the Dalhousie University SLOWPOKE-2 reactor (DUSR) facility and anti-coincidence gamma-ray spectrometry.

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solid-phase extraction (SPE), gel permeation chromatography (GPC), solid-phase microextraction (SPME), QuEChERS, dispersive-solid phase extraction (d-SPE) and matrix solid-phase dispersion (MSPD) have been attempted to eliminate lipids and co

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Abstract  

The use of solid phase extraction (SPE) disks was studied for the quantification of selected radionuclides in aqueous solutions. The extraction of four radionuclides using six types (two commerical, four test materials) of 3M EmporeTM RAD disks was studied. The radionuclides studied were: technetium-99 (two types of disks), cesium-137 (two types), strontium-90 (one type), plutonium-238 (one type). Extractions were tested from DI water, river water and seawater. Extraction efficiency, kinetics (flow rate past the disk), capacity, and potential interferences were studied as well as quantification methods.

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Acta Chromatographica
Authors: Stefano Dugheri, Giorgio Marrubini, Nicola Mucci, Giovanni Cappelli, Alessandro Bonari, Ilenia Pompilio, Lucia Trevisani, and Giulio Arcangeli

understand the working principles of the various techniques, to maximize the process, and obtain optimum results [ 1, 2 ]. Solid-phase extraction (SPE) is a technique that can be used for sample preparation and clean-up, providing the isolation, extraction

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, and the main pretreatment methods for detecting and analyzing organochlorines in water samples are liquid-liquid extraction [ 9, 10 ], solid-phase extraction (SPE) [ 11 ], and Soxhlet extraction [ 12 ]. SPE is a relatively new sample pretreatment

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instrumental analysis is one of the most crucial steps in the overall analytical process. Generally, liquid–liquid extraction (LLE) and solid-phase extraction (SPE) are considered as the most commonly used techniques for the preconcentration of compounds from

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solid phase extraction (d-SPE) is based on the addition of the sorbent material into the extract to remove the matrix concomitants. d-SPE is another novel sample preparation technique which offers unique advantages such as simplicity, low solvent use

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Abstract  

This paper reports silica gel loaded with p-tert-butylcalix[8]arene as a new solid phase extractor for determination of trace level of uranium. Effective extraction conditions were optimized in column methods prior to determination by spectrophotometry using arsenazo(III). The results showed that U(VI) ions can be sorbed at pH 6 in a mini-column and quantitative recovery of U(VI) (>95–98%) was achieved by stripping 0.4 mol L−1 HCl. The sorption capacity of the functionalized sorbent is 0.072 mmol uranium(VI) g−1 modified silica gel. The relative standard deviation and detection limit were 1.2% (n = 10) for 1 μg uranium(VI) mL−1 solution and 0.038 μg L−1, respectively. The method was employed to the preconcentration of U(VI) ions from spiked ground water samples.

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Quantitative determination of the antibiotics enrofloxacin, oxytetracycline, and trimethoprim in aquatic samples is reported. The method involves solid-phase extraction (SPE) and preconcentration of the antibiotics, separation by thin-layer chromatography (TLC) and quantification by video densitometry. TLC separation was performed on HPTLC CN F 254 s plates with H 2 C 2 O 4 -methanol as mobile phase. Spots were detected and quantified at λ = 254 nm by videodensitometry. Limits of detection ( LOD ) and limits of quantification ( LOQ ) for TLC determination were calculated. The method was evaluated for spiked water samples. Antibiotics were extracted by solid-phase extraction (SPE) on a polystyrene-divinyl-benzene (SDB) Empore extraction disk. The extraction efficiency was checked by recovery experiments.

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Abstract  

Solid-phase extraction disks produced by 3M and Eichrom were evaluated for routine use in supporting the Hanford Groundwater Monitoring Project. Both disk formats contain Sr- or Tc-selective extractants, bound in a filter support, that act to preconcentrate and isolate the isotope of interest. The 3M Empore Sr Rad Disks and Tc Rad Disks were tested with respect to precision, accuracy, radiochemical yields, interferences, and volume-load variation. The Empore and Eichrom solid-phase extraction disks were applied to the 90Sr and/or 99Tc determination in representative Hanford groundwater samples with varying chemical and isotopic compositions. Results were compared to standard analytical methods. Both the Empore and Eichrom Tc extraction disks produced consistently higher radiochemical yields, lower detection limits, and greater accuracy than the standard analysis method. The Empore Sr extraction disks produced comparable radiochemical yields, detection limit, and accuracy relative to the standard method; however, total uncertainties were lower.

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