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1.
New preservation method for inorganic arsenic speciation in acid mine drainage samples 总被引:5,自引:0,他引:5
A new preservation method has been proposed for the speciation of As(III) and As(V) in acid mine drainage (AMD) samples, characterised by low pH and high metallic content. Samples were taken from a polymetallic sulphides mining area in the province of Huelva (SW Spain), under exploitation until the 1960s for its Cu, Pb and Zn sulphides. The abandoned mine works and the numerous waste rocks heaps produce AMD with high As content, an aqueous pollution source for the nearby streams. Short-term (from few hours to 1 week) preservation of the two inorganic arsenic species was studied, trying different containers (polyethylene, glass), presence or absence of light, temperatures (ambient, refrigerated, frozen), preserving agents and procedures (EDTA, HCl or AcH acids, cation-exchange resin). The speciation results obtained by liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) indicated a rapid conversion of the samples with most of the preservation procedures reported in the literature after 3 h after sample collection. A promising method for arsenic preservation has been developed in this work, which maintains the arsenic species distribution in the original samples for a longer time. It consists in the use of opaque glass containers, acidification of the samples with HCl and in situ cleanup with cationic exchange resin, which allowed to preserve the samples for As speciation for at least 48 h. 相似文献
2.
Gisele B. Tonietto José M. Godoy Ana Cristina Oliveira Marcia V. de Souza 《Analytical and bioanalytical chemistry》2010,397(5):1755-1761
High-performance liquid chromatography (HPLC) coupled to an ICP-MS with an octapole reaction system (ORS) has been used to
carry out quantitative speciation of selenium (Se) and arsenic (As) in the stream waters of a refining process. The argon
dimers interfering with the 78Se and 80Se isotopes were suppressed by pressurizing the octapole chamber with 3.1 mL min−1 H2 and 0.5 mL min−1 He. Four arsenic species arsenite—As(III), arsenate (As(V)), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)—and
three inorganic Se species—selenite Se(IV), selenate Se(VI), and selenocyanate (SeCN−)—were separated in a single run by ion chromatography (IC) using gradient elution with 100 mmol L−1 NH4NO3, pH 8.5, adjusted by addition of NH3, as eluent. Repeatabilities of peak position and of peak area evaluation were better than 1% and about 3%, respectively.
Detection limits (as 3σ of the baseline noise) were 81, 56, and 75 ng L−1 for Se(IV), Se(VI), and SeCN−, respectively, and 22, 19, 25, and 16 ng L−1 for As(III), As(V), MMA, and DMA, respectively. Calibration curve R
2 values ranged between 0.996 and 0.999 for the arsenic and selenium species. Column recovery for ion chromatography was calculated
to be 97 ± 6% for combined arsenic species and 98 ± 3% for combined selenium species. Because certified reference materials
for As and Se speciation studies are still not commercially available, in order to check accuracy and precision the method
was applied to certified reference materials, BCR 714, BCR 1714, and BCR 715 and to two different refinery samples—inlet and
outlet wastewater. The method was successfully used to study the quantitative speciation of selenium and arsenic in petroleum
refinery wastewaters. 相似文献
3.
Panayot K. Petrov Jožica Majda Serafimovska Sonja Arpadjan Dimiter L. Tsalev Trajče Stafilov 《Central European Journal of Chemistry》2008,6(2):216-221
The influence of EDTA, carboxylic acids, amino-and hydroxocarboxylic acids, monosaccharides and humic substances on the generation
of arsines in hydride generation atomic absorption spectrometry (HGAAS) was investigated. EDTA (0.02 mol L−1), ascorbic acid (0.02 mol L−1) and glucose or fructose (0.2 mol L−1) are useful additives for levelling sensitivities for As(III), monomethylarsonate (MMA) and dimethylarsinate (DMA). The presence
of glycine, malonic, tartaric acids, BICIN and soil humin extracts leads to differences in analytical signal response between
these arsenic species. An analytical application to the determination of the sum of As(III), monomethylarsonate (MMA) and
dimethylarsinate (DMA) as well as the sum of toxicologically relevant hydride forming arsenic fraction As(III) + As(V) + MMA
+ DMA in EDTA soil/sediment extracts using continuous flow HGAAS was demonstrated. The limit of detection was 0.2 mg kg−1 As. Within-day and between-day precision were in the range 3–7% and 4–10%, respectively, for arsenic contents of 0.7–25 mg
kg−1, with recoveries 95–103%.
相似文献
4.
W. D. James T. Raghvan T. J. Gentry G. Shan R. H. Loeppert 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):267-270
Sensitivities for the measurement of four arsenic species, AsIII, AsV, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), in environmental waters and rice extracts by a new neutron
activation analysis (NAA) method using pre-separation of the species by liquid chromatography were determined. A manual fraction
collection was used to isolate the species, followed by instrumental neutron activation analysis procedures. The sensitivities
determined for arsenic species in the samples varied from 1.21 to 1.47 ng per vial or about 30 μg·L−1 in sample solutions which translates to about 900 ng arsenic per gram of rice for our HPLC-NAA experiments. 相似文献
5.
Mihucz VG Tatár E Virág I Cseh E Fodor F Záray G 《Analytical and bioanalytical chemistry》2005,383(3):461-466
Flow injection analysis (FIA) and high-performance liquid chromatography double-focusing sector field inductively coupled
plasma mass spectrometry (HPLC-DF-ICP-MS) were used for total arsenic determination and arsenic speciation of xylem sap of
cucumber plants (Cucumis sativus L.) grown in hydroponics containing 2 μmol dm−3 arsenate or arsenite, respectively. Arsenite [As(III)], arsenate [As(V)] and dimethylarsinic acid (DMA) were identified in
the sap of the plants. Arsenite was the predominant arsenic species in the xylem saps regardless of the type of arsenic treatment,
and the following concentration order was determined: As(III) > As(V) > DMA. The amount of total As, calculated taking into
consideration the mass of xylem sap collected, was almost equal for both treatments. Arsenite was taken up more easily by
cucumber than arsenate. Partial oxidation of arsenite to arsenate (<10% in 48 h) was observed in the case of arsenite-containing
nutrient solutions, which may explain the detection of arsenate in the saps of plants treated with arsenite. 相似文献
6.
Summary An ion-chromatographic procedure is described for the determination of selenium (VI) at μg L−1 level in the presence of anions and heavy metal ions. Maximum permissible concentrations and effects from each interfering
substance were investigated for the Se concentration range 12.5–1,000 μg L−1. The method, optimized for the detection of SeO
4
2−
, gives results suitable for speciation analysis. Total selenium can be determined after complete conversion to selenate ion
by oxidation with KMnO4. The detection limit of selenium is 4.8 μg L−1 (0.96 ng for 200 μL sample).
Paper presented at the 41st Pittsburgh Conference, New York, March 5–9, 1990. 相似文献
7.
W. Menendez Sanchez B. Zwicker A. Chatt 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(1):133-138
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. 相似文献
8.
W. Clay Davis Rolf Zeisler John R. Sieber Lee L. Yu 《Analytical and bioanalytical chemistry》2010,396(8):3041-3050
Two independent liquid chromatography inductively coupled plasma-mass spectrometry (LC/ICP-MS) methods for the separation
of arsenic species in urine have been developed with quantification by standard additions. Seven arsenic species have been
quantified in a new NIST frozen human urine Standard Reference Material (SRM) 2669 Arsenic Species in Frozen Human Urine,
Levels 1 and 2. The species measured were: arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA), dimethylarsinate
(DMA), arsenobetaine (AB), arsenocholine (AC), and trimethylarsine oxide (TMAO). The purity of each arsenic standard used
for quantification was measured as well as the arsenic species impurities determined in each standard. Analytical method limits
of detection (L
D) for the various species in both methods ranged from 0.2 to 0.8 μg L−1 as arsenic. The results demonstrate that LC/ICP-MS is a sensitive, reproducible, and accurate technique for the determination
of low-level arsenic species in urine. Measurements of the arsenic species 3 years after initial production of the SRM demonstrate
the stability of the arsenic species in the urine reference material. 相似文献
9.
Arsenic(III) was preconcentrated in a flow-through electrochemical cell on a gold coated porous carbon electrode. On stripping,
arsenic was eluted with diluted nitric acid and determined off-line by GF AAS. The deposition and stripping steps were optimized.
The limit of detection and limit of quantification were found to be 1.9 μg L−1 and 6.4 μg L−1, respectively. The repeatability and reproducibility were found to be 5.3 % and 9.3 %, respectively. Total arsenic was determined
after a microwave assisted chemical reduction of As(V) to As(III) making the procedure suitable for speciation analysis. The
method was applied in analysis of water samples. 相似文献
10.
M.N. Matos Reyes M.L. Cervera R.C. Campos M. de la Guardia 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007
A fast, sensitive and simple non-chromatographic analytical method was developed for the speciation analysis of toxic arsenic species in cereal samples, namely rice and wheat semolina. An ultrasound-assisted extraction of the toxic arsenic species was performed with 1 mol L− 1 H3PO4 and 0.1% (m/v) Triton XT-114. After extraction, As(III), As(V), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) concentrations were determined by hydride generation atomic fluorescence spectrometry using a series of proportional equations corresponding to four different experimental reduction conditions. The detection limits of the method were 1.3, 0.9, 1.5 and 0.6 ng g− 1 for As(III), As(V), DMA and MMA, respectively, expressed in terms of sample dry weight. Recoveries were always greater than 90%, and no species interconversion occurred. The speciation analysis of a rice flour reference material certified for total arsenic led to coherent results, which were also in agreement with other speciation studies made on the same certified reference material. 相似文献
11.
A simple continuous flow method is proposed to eliminate copper interference in arsenic speciation by hydride generation, based on the selective retention of this interfering ion in an iminodiacetate chelating resin previous to the hydride generation process. The arsines generated were cold trapped and measured by ICP/OES. The proposed method allows about 98% of the copper present in the samples to be removed. Minor co-retention of As(V) was observed as a result of electrostatic interaction between the arsenate anion and the nitrogen of the iminodiacetate group of the chelating resin Muromac A-1, the charge distribution of which is modified when copper is chelated. The species As(III), MMA and DMA were not retained in the microcolumn, probably because these species are mainly in the molecular form at the working pH value (4.5). In synthetic samples containing 50 g l–1 of each arsenic species together with 100 mg l–1 copper, the recoveries obtained were: As(V) 97.6%, As(III) 100%, MMA 99.8%, and DMA 99.9%. The method was applied to arsenic speciation in river water samples containing high levels of copper. 相似文献
12.
Youqing Shi R. Acharya A. Chatt 《Journal of Radioanalytical and Nuclear Chemistry》2004,262(1):277-286
Neutron activation analysis (NAA) in combination with mainly high-performance liquid chromatography (HPLC) has been developed
for the determination of low levels of five arsenic species, namely As(III), As(V), monomethylarsonic acid (MMA), dimethylarsinic
acid (DMA), and arsenobetaine (AsB) in water samples. Organically bound arsenic (OBAs) and total arsenic have also been determined.
In addition to anion-exchange HPLC, solid phase extraction and open-column cation-exchange chromatographic methods have also
been used. The detection limits of the method have been found to be 0.005 ng·cm−3 for OBAs, 0.02 ng·cm−3 for AsB, DMA, MMA, As(III), and As(V) and 0.12 ng·cm−3 for total arsenic.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
Arsenic compounds including arsenous acid (As(III)), arsenic acid (As(V)), dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA) were separated by high-performance liquid chromatography (HPLC) and detected by inductively coupled plasma mass spectrometry (ICP-MS). A Hamilton PRX-100 anionic-exchange column and a pH 8.5 K2HPO4/KH2PO4 5.0 × 10−3 mol L−1 mobile phase were used to achieve arsenic speciation. The separation of arsenic species provided peaks of As(III) at 2.75 min, DMA at 3.33 min, MMA at 5.17 min and As(V) at 12.5 min. The detection limits, defined as three times the standard deviation of the lowest standard measurements, were found to be 0.2, 0.2, 0.3 and 0.5 ng mL−1 for As(III), DMA, MMA and As(V), respectively. The relative standard deviation values for a solution containing 5.0 μg L−1 of As(III), DMA, MMA and As(V) were 1.2, 2.1, 2.5 and 3.0%, respectively. This analytical procedure was applied to the speciation of arsenic compounds in drinking (soft drink, beer, juice) samples. The validation of the procedure was achieved through the analysis of arsenic compounds in water and sediment certified reference materials. 相似文献
14.
Arsenic-speciation analysis in marine samples was performed by high-pressure liquid chromatography (HPLC) with ICP–MS detection.
Separation of eight arsenic species—AsIII, MMA, DMA, AsV, AB, TMAO, AC and TeMAs+—was achieved on a C18 column with isocratic elution (pH 3.0), under which conditions AsIII and MMA co-eluted. The entire separation was accomplished in 15 min. The HPLC–ICP–MS detection limits for the eight arsenic
species were in the range 0.03–0.23 μg L−1 based on 3σ for the blank response (n=5). The precision was calculated to be 2.4–8.0% (RSD) for the eight species. The method was successfully applied to several
marine samples, e.g. oysters, fish, shrimps, and marine algae. Low-power microwave digestion was employed for extraction of
arsenic from seafood products; ultrasonic extraction was employed for the extraction of arsenic from seaweeds. Separation
of arsenosugars was achieved on an anion-exchange column. Concentrations of arsenosugars 2, 3, and 4 in marine algae were
in the range 0.18–9.59 μg g−1.
This paper was presented at the European Winter Conference 2005 相似文献
15.
Amereih S Meisel T Kahr E Wegscheider W 《Analytical and bioanalytical chemistry》2005,383(7-8):1052-1059
Speciation analysis of Sb(III) and Sb(V) in a soil sample was performed through extraction and on-line isotope dilution concentration
determination after a chromatographic separation. The total Sb concentration found in a through traffic contaminated soil
sample was (4.17 μg g−1, 0.3 μg g−1 SD, n=6). It was determined using ICP-MS after soil digestion using the sodium peroxide sintering method. The optimized extraction
procedure for speciation analysis was carried out using 100 mmol L−1 citric acid at pH 2.08 by applying an ultrasonic bath for 45 min at room temperature. The effects of citric acid concentration
(0–500 mmol L−1), pH (1–6), and temperature (30–60°C) on inorganic antimony species distribution in the examined sample were studied and
optimized. The separation of Sb(III) and Sb(V) was achieved using an anion exchange column (PRP-X100) and 10 mmol L−1 EDTA and 1 mmol L−1 phthalic acid at pH 4.5 as a mobile phase. The eluent from the HPLC was mixed with an enriched (94.2%) 123Sb spike solution that was pumped by a peristaltic pump with a constant flow rate (0.5 mL min−1) in a three-way valve. The blend passed directly to the Conikal nebulizer of the ICP-MS. By using the above extraction procedure
and methodology, 43.2% Sb(V) (2.9% RSD, n=3) and 6.0% Sb(III) (1.3% RSD, n=3) of total Sb found in the sample could be detected. The detection limits achieved by the proposed method were 20 ng L−1 and 65 ng L−1 for Sb(V) and Sb(III), respectively. The precision, evaluated by using RSD with 100 ng L−1 calibration solutions, was 2.7% and 3.2% (n=6) for Sb(V) and Sb(III), respectively, in aqueous solutions. 相似文献
16.
Sánchez-Rodas D Luis Gómez-Ariza J Oliveira V 《Analytical and bioanalytical chemistry》2006,385(7):1172-1177
A rapid extraction procedure has been developed for speciation of arsenic in chicken tissue. Water, methanol–water (1:1),
and methanol–chloroform (1:1) were tested as extraction media. Individual use of an ultrasonic bath, a microwave oven, or
an ultrasonic probe was not sufficient for quantitative recovery of As(III), dimethylarsinate, monomethylarsonate, As(V),
and arsenobetaine in spiked samples of chicken tissue. A new extraction procedure using a methanol–water mixture and a microwave
oven then an ultrasonic probe enabled extraction of the arsenic species in 7 min with efficiencies ranging from 80 to 100%.
HPLC–UV–HG–AFS was used for the determinations. The extraction procedure was 100% efficient when applied to real samples of
chicken tissue. AsB (48±5 μg As kg −1) and one containing-arsenic feed additive, Nitarsone (227±5 μg As kg −1) were detected. 相似文献
17.
Summary Capillary zone electrophoresis (CZE) has been coupled with mass spectrometry to enable the identification of mineral and organometallic
compounds of arsenic in speciation studies. The electrophoretic effluent was introduced through a concentric interface into
the mass spectrometer. Make-up liquid was added to enable electric contact at the outlet of the separation capillary and to
assist the electronebulization process. After ionization, the ions were analyzed and quantified with an ion-trap detector.
Optimization of the coupling conditions (geometry of the concentric interface, composition and flow rate of the sheath liquid,
electronebulization and detection conditions) is described. The results show that the geometry of the concentric interface
and the positioning of the outlet of the separation capillary have a critical effect on stability and sensitivity.
Programming the electronebulization and detection conditions throughout the analysis enabled identification and quantification
of the seven arsenic compounds of interest (neutral, and positively or negatively charged species) in less than 20 min at
the ppm level. Limits of detection ranged from 0.5 to 3.3 mg L−1, corresponding to amounts injected ranging from 15 to 60 pg. The linear dependence of mass spectrometric response on arsenic
concentration was verified for concentrations ranging from 5 to 200 mgL−1. For the two positively charged species, arsenobetaine and arsenocholine, an on-line preconcentration technique (field-amplified
sample injection) enabled reduction of the detection limits by approximately one order of magnitude to 110 and 160 μgL−1, respectively. 相似文献
18.
Guzmán-Vázquez de Prada A Loaiza OA Serra B Morales D Martínez-Ruiz P Reviejo AJ Pingarrón JM 《Analytical and bioanalytical chemistry》2007,388(1):227-234
A molecularly imprinted polymer was developed and used for solid-phase extraction (MISPE) of the antihelmintic fenbendazole
in beef liver samples. Detection of the analyte was accomplished using square wave voltammetry (SWV) at a cylindrical carbon
fibre microelectrode (CFME). A mixture of MeOH/HAc (9:1) was employed both as eluent in the MISPE system and as working medium
for electrochemical detection of fenbendazole. The limit of detection was 1.9 × 10−7 mol L−1 (57 μg L−1), which was appropriate for the determination of fenbendazole at the maximum residue level permitted by the European Commission
(500 μg kg−1 in liver). Given that the SW voltammetric analysis could not be directly performed in the sample extract as a consequence
of interference from some sample components, a sample clean-up with a MIP for selectively retaining fenbendazole was performed.
The MIP was synthesized using a 1:8:22 template/methacrylic acid/ethylene glycol dimethacrylate ratio. A Britton–Robinson
Buffer of pH 9.0 was selected for retaining fenbendazole in the MIP cartridges, and an eluent volume of 5.0 mL at a flow rate
of 2.0 mL min−1 was chosen in the elution step. Cross-reactivity with the MIP was observed for other benzimidazoles. The synthesized MIP
exhibited a good selectivity for benzimidazoles with respect to other veterinary drugs. The applicability of the MISPE-SWV
method was tested with beef liver samples, spiked with fenbendazole at 5,000 and 500 μg kg−1. Results obtained for ten different liver samples yielded mean recoveries of (95 ± 12)% and (96 ± 11)% for the upper and
lower concentration level, respectively. 相似文献
19.
López-Darias J Pino V Ayala JH González V Afonso AM 《Analytical and bioanalytical chemistry》2008,391(3):735-744
An environmentally friendly method to extract endocrine-disrupting phenols (EDPs) from seawaters was realized using nonionic
surfactant mixtures and micelle-mediated extractions. The preconcentration step was achieved directly in the seawater matrix,
and was followed by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection without any clean-up steps
to remove the surfactant mixture prior to injection. Various nonionic surfactant mixtures were used, and polyoxyethylene-10-laurylether
(POLE) with polyoxyethylene-4-laurylether (Brij 30) was found to be the best to work with. Method optimization involved maximizing
the preconcentration factor using the studied mixtures. The proposed method gave extraction recoveries ranging from 83.3 to
114.4% for an EDP spiking level of 46.7 μg L−1, and from 63.4 to 112.4% for a spiking level of 4.7 μg L−1 for EDPs studied in real seawater matrices, with relative standard deviations of <12.1%. The detection limits of the method
varied from 0.18 μg L−1 for bisphenol A (BPA) to 1.17 μg L−1 for 4-cumylphenol (4-CP). The method was applied to seawaters from the Canary Islands with successful results.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
20.
Karadjova IB Lampugnani L D'Ulivo A Onor M Tsalev DL 《Analytical and bioanalytical chemistry》2007,388(4):801-807
A rapid, accurate, and precise method is described for the determination of Pb in wine using continuous-flow hydride generation
atomic fluorescence spectrometry (CF-HGAFS). Sample pretreatment consists of ten-fold dilution of wine followed by direct
plumbane generation in the presence of 0.1 mol L−1 HCl and 1% m/v K3[Fe(CN)6] with 1% m/v NaBH4 as reducing agent. An aqueous standard calibration curve is recommended for Pb quantification in wine sample. The method
provides a limit of detection and a limit of quantification of 0.3 μg L−1 and 1 μg L−1, respectively. The relative standard deviation varies between 2–6% (within-run) and 4–11% (between-run) at 3–30 μg L−1 Pb levels in wine. Good agreement has been demonstrated between results obtained by CF-HGAFS and direct electrothermal atomic
absorption spectrometry in analyses of red and white wines within the concentration range of 9.2–25.8 μg L−1 Pb. 相似文献