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A novel and simple trap technique combining a gold‐coated tungsten coil with hydride generation atomic absorption spectrometry (HGAAS) were developed for ultra‐trace lead determination. The technique was based on first transporting the plumbane produced by the HG system, together with H2, to a trap externally heated to 92 °C, where it was collected for in‐situ preconcentration and then volatilized by raising the trap temperature to 510 °C. For a 120 s trapping time, the limit of detection (LOD) was 2.9 ng L−1, the limit of quantification (LOQ) was 9.7 ng L−1 and the relative standard deviation was 3.1 % (at 0.02 μg L−1). The analytical performance of the technique was contrasted against the classical HGAAS method and a 39.2‐fold increase in sensitivity was obtained when comparing the characteristic concentrations of both methodologies. The morphology of the trap surface was also studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The accuracy of the proposed method was verified by analyzing the Pb concentration in the certified reference materials and the results agreed well with the certified values. Finally, the developed procedure was successfully applied to seawater samples and the recoveries of standard addition were between 102.4 % and 105.2 %. [ABSTRACT FROM AUTHOR]

In recent decades, tattooing has become a form of social and artistic expression. To apply a tattoo, the skin is marked by the internal injection of ink in the skin. Hence, it includes human health exposure to metals since the tattoo ink composition includes such elements. The present paper reports the determination and quantification of 8 elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb) in twenty tattoo ink colors available in the Greek market imported from the USA and China. The elemental content was carried out by atomic absorption spectrometry after microwave-assisted digestion. A comparison was carried out between the results of the present study and the maximum permitted concentrations as proposed in the ResAP and EPA guidelines, while the level of dermal exposure due to pigment application through ink injection was also estimated. All inks contained Cr, Cu, Ni, and Pb, while the content of As, Cd, and Co was below the detection limit in certain samples. Mercury was determined in three samples. Chromium, Cu, and Ni were present in the highest concentrations, while Cd and Hg contents were in general low. Most elements presented their maximum levels in the brown ink originating from USA. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sb speciation analysis is important in relation to industrial exposure or environmental release because of the large difference in toxicity between SbIII and SbV. In this study, the release of Sb species from a semiconductor material (undoped and Bi-doped InSb thin films) in 0.1 mol/L sodium acetate buffer was investigated using hydride generation–microwave plasma-atomic emission spectroscopy (HG–MP-AES). Total Sb was determined using our previously reported method, and SbIII concentration was measured without reduction by potassium iodide and with a lower sodium tetrahydroborate/sodium hydroxide concentration. To estimate the SbV concentration, the SbIII concentration was subtracted from the total Sb concentration. The Sb species were not changed by Bi doping, even though Bi doping suppressed the Sb elution from the thin films. A large fraction of Sb eluted as SbIII during leaching for 28 days. This is the first Sb speciation analysis using HG–MP-AES of eluates from Sb-based materials. Sb speciation analysis using HG–MP-AES is cost effective, reliable, and requires only simple sample preparation. [ABSTRACT FROM AUTHOR]

This paper considers the features of determining the total tin content in waters with different salinity. Direct ICP-spectrometric analysis of sea waters with a salinity of more than 6‰ significantly reduced the analytical signal of tin by 70% (ICP-MS) and 30% (ICP-OES). The matrix effect of macrocomponents was eliminated by generating hydrides using 0.50 M sodium borohydride and 0.10 M hydrochloric acid. The effect of transition metals on the formation of tin hydrides was eliminated by applying L-cysteine at a concentration of 0.75 g/L. The total analyte concentrations, considering the content of organotin compounds, were determined after microwave digestion of sample with oxidizing mixtures based on nitric acid. The generation of hydrides with the ICP-spectrometric determination of tin leveled the influence of the sea water matrix and reduced its detection limit from 0.50 up to 0.05 µg/L for all digestion schemes. The developed analysis scheme made it possible to determine the total content of inorganic and organic forms of tin in sea waters. The total content of tin was determined in the waters of the Azov and Black seas at the levels of 0.17 and 0.24 µg/L, respectively. [ABSTRACT FROM AUTHOR]

An analytical method with no need for laborious sample preparation before determining the total Sn in canned tomatoes by hydride generation (HG) coupled to inductively coupled plasma optical emission spectrometry (ICP OES) was developed. The ultrasound-assisted extraction with various reagents (acidic media: HCl, HNO3, CH3COOH or aqua regia and alkaline: TMAH) that could replace the traditional wet sample digestion in the presence of a concentrated HNO3-H2O2 mixture was tested and compared. Tin hydride was generated directly from the prepared sample solution in the reaction with 1% NaBH4 or via prior acidification with a 1 mol L−1 HCl. The effect of the sample pretreatment before HG-ICP OES measurements on the Sn signal was also examined. The best results were obtained with aqua regia as the extraction medium, followed by a simple two-fold dilution of the sample extract combined with the addition of L-cysteine. The developed method was characterized by a detection limit of Sn at 0.74 ng g−1, a precision of better than 6%, and a trueness, verified by the analyte spike-and-recovery test, of 98.4–104%. Its usefulness was demonstrated by the determination of Sn in seven canned tomatoes. [ABSTRACT FROM AUTHOR]

A miniaturized/portable dual-mode colorimetric analytical system was established for inorganic arsenic determination in honey and drinking water samples. Hydride generation (HG) was utilized as a sampling technique for this colorimetric system, because of its high generation efficiency and efficient matrix separation. AsH3 was generated via HG and then reacted with HAuCl4, gold nanoparticles (Au NPs) were formed on the paper sheet, leading the paper color changed from light yellow to dark blue, it could be readout by naked-eye (visual colorimetric mode) and a smartphone (RGB readout mode) simultaneously. The accuracy and potential application for field analysis were further confirmed by the analysis of two water samples, four honey samples and two certified reference water samples (BWB2440-2016 and GBW08650), good recoveries (90–116%) were obtained for those samples and their spiked samples.

[Display omitted] • Metal organic framework (Ag-MOF) was used as substrate. • Hydride generation-smartphone colorimetric system was established. • Speciation analysis of inorganic antimony was achieved. • Smartphone mode and visual mode was used simultaneously. A portable and easy-use analytical system was established for speciation analysis of inorganic antimony (Sb(III) and Sb(V)) based on hydride generation-smartphone colorimetric method. Metal organic framework (Ag-MOF) was served as substrate here. Sb(III) was transformed to stibine (SbH 3) during hydride generation process, SbH 3 was then transported and reacted with Ag-MOF in reaction bottle, leading to its color turn to black from light gray, the variance was then distinguished by visual and smartphone mode. A detectable limit as low as 0.01 μg/mL can be readout by smartphone mode. Besides, citric acid was used as masking reagent for speciation analysis of Sb(III) and Sb(V). Several real environmental water samples were further detected using this colorimetric system and recoveries for those samples were 90–106 %. The potential application of this method for rapid and field analysis of inorganic antimony was further demonstrated by analysis of a certified reference water sample (BWZ6657-2016B). [ABSTRACT FROM AUTHOR]

A sensitive and isotopic interference-free analysis method for Sb was developed based on hydride generation-microwave plasma torch-mass spectrometry (HG-MPT-MS). Compared to the conventional ICP-MS, MPT coupled to an ion trap mass spectrometer enabled much "softer" ionization of Sb under ambient condition, which provided multi-detection modes and various ion forms, such as Sb+, SbO+, SbO 2 −, SbO++H 2 O and so on. These ion formations can be easily regulated by tuning capillary voltage and tube lens voltage, which facilitated elimination of isotopic interference during analysis, for instance the interference of 123Te on 123Sb could be effectively excluded by optimizing parameters of capillary voltage and tube lens voltage. The potential application of HG-MPT-MS for Sb isotope ratio analysis was also demonstrated, which could be determined in different forms, e.g., 123Sb/121Sb or 123Sb16O/121Sb16O. The value of 123Sb/121Sb was determined to be 0.75110 ± 0.00038 (2σ, n > 50). In addition, the detection limit, linearity and spike recovery were also studied. Overall, HG-MPT-MS performed equally well on detection limit (0.05 μg/L) with ICP-MS or HG-AFS. The linearity (R2 = 0.998) was checked in the concentration range of 10–500 μg/L. Spike recovery were evaluated with two soil samples, and the obtained spike recovery ranged 90–100 %. In general, HG-MPT-MS was expected to be a versatile tool for study the biochemical or geochemical behaviors of Sb and other hydride forming elements under ambient condition in a much simpler and more efficient way. [Display omitted] • The method features isotopic interference-free analysis for Sb. • The method enabled sensitive MS analysis of Sb under ambient conditions. • The method provided multi-detection modes and various ion forms for Sb. • HG-MPT-MS was a potential tool for Sb isotope ratio analysis. [ABSTRACT FROM AUTHOR]

This work describes the intricacies of the determination of the trimethylselenonium ion (TMSe) in human urine via high-performance liquid chromatography–hydride generation–atomic fluorescence spectrometry (HPLC-HG-AFS). By definition, this technique requires that the separated TMSe can be online converted into a volatile compound. Literature data for the determination of TMSe via the hydride generation technique are contradictory; i.e., some authors claim that direct formation of volatile compounds is possible under reduction with NaBH4, whereas others reported that a digestion step is mandatory prior to conversion. We studied and optimized the conditions for online conversion by varying the mobile phase composition (pyridine, phosphate, and acetate), testing different reaction coils, and optimizing the hydride generation conditions, although technically no hydride (H2Se) is formed but a dimethylselenide (DMSe). The optimized conditions were used for the analysis of 64 urine samples of 16 (unexposed) volunteers and the determination of low amounts of TMSe (LOD = 0.2 ng mL−1). Total (specific gravity–corrected) selenium concentrations in the urine samples ranged from 7.9 ± 0.7 to 29.7 ± 5.0 ng mL−1 for individual volunteers. Four volunteers were characterized as TMSe producers (hINMT genotype GA) and 12 were non-producers (hINMT genotype GG). Urine of TMSe producers contained 2.5 ± 1.7 ng mL−1 of TMSe, compared to 0.2 ± 0.2 ng mL−1 for non-producers. [ABSTRACT FROM AUTHOR]

Environmental context: Arsenic can be found in all environmental compartments in a large number of chemical forms of varying toxicity. We performed an inter-laboratory comparison study focusing on quantitation of some of the most toxic arsenic forms in seven different biological materials and found very good agreement among the submitted results. Certification of the studied materials will provide suitable quality control samples for environmentally relevant concentrations of arsenic in food products and biota. Rationale: Arsenic (As) speciation analysis in biological matrices has been performed for several decades; however, there are very few matrix certified reference materials available for the validation of analytical methods. The literature data on the mass fractions of As species in the existing certified reference materials are inconsistent and suggest method extraction dependency. Methodology: In the present study, an international round-robin study was organised to identify the possible sources of discrepancies in quantitation of several As species in different matrices of biological reference materials: one plant tissue, three marine and three terrestrial biological tissues. Each participating laboratory was provided with a set of identical calibration standard solutions, and analysed the samples by following a common group extraction method as well as using an in-house protocol. Results: The results showed that significant biases can be introduced by insufficient verification of the analyte's mass fractions in the calibration standard solutions. The choice of extraction method seems to have very little impact on the quantitation of As species in the studied plant and terrestrial biological tissues. However, following a prescribed extraction method led to significant reduction of uncertainties in more complex samples such as marine animal tissues. Discussion: Some differences in the mass fractions of As species extracted from marine animal tissues in water (with and without H2O2) were observed and should be further investigated. Despite the variety of extraction methods used, very good agreement between reported mass fractions was achieved and the combined consensus values will be published as certified reference values of As species in the studied materials. Environmental context. Arsenic can be found in all environmental compartments in a large number of chemical forms of varying toxicity. We performed an inter-laboratory comparison study focusing on quantitation of some of the most toxic arsenic forms in seven different biological materials and found very good agreement among the submitted results. Certification of the studied materials will provide suitable quality control samples for environmentally relevant concentrations of arsenic in food products and biota. [ABSTRACT FROM AUTHOR]

[Display omitted] A low-power-driven and carrier-gas free arc igniter microplasma optical emission spectrometry (AIM-OES) was coupled with hydride generation (HG) to detect arsenic in soils, only utilizing by-product H 2 produced therein as a working gas. • A low-power-driven arc igniter microplasma optical emission spectrometry (AIM-OES) was fabricated for determining arsenic in soils. • The by-product, H 2 , formed by hydride generation (HG) process acted as the sole working gas for the construction of a miniaturized, carrier-gas free device. • The discharges in air and Ar, with and without hydrogen content (from the HG step) were systematically studied. Rapid on-site assessment of arsenic contamination in soils is crucial for environmental protection and human health. In order to build an effective and affordable device for the determination of arsenic, the use of carrier gas supplies and high power energy consumption largely limit the miniaturization of microplasma-based optical emission spectrometry (OES). An arc igniter microplasma (AIM) can be powered by a low DC power supply and operated in the atmosphere of air without gas infusion, which is beneficial to construct a carrier-gas free and low power supply setup. Hydride generation (HG) can improve sample transport efficiency and reduce matrix effects, but the generated by-product hydrogen has not been explored as a sole working gas for plasma excitation. In this work, a hydride generation arc igniter microplasma optical emission spectrometer (HG-AIM-OES) was fabricated for detecting arsenic in soils. H 2 derived from HG was served as a working gas to transport AsH 3 to excite, eliminating the use of a carrier gas unit. Under the optimized operating conditions, the limit of detection (LOD) for arsenic was 164 μg/L (the analytical line at 234.98 nm), and good linearity of the method was achieved in the range of 0.5–20 mg/L with a precision of 3.14 % (the concentration of arsenic at 1 mg/L). In addition, the influence of H 2 on AIM physical properties was carefully studied in the air and Ar discharge atmospheres. The accuracy of the proposed device was validated by the analysis of certified reference materials (CRMs) and a real soil sample, resulting in good agreement with the obtained results by air and Ar as working gas. This HG-AIM-OES system provides a miniaturized, carrier gas-free and low power consuming tool for monitoring and assessment of arsenic-contaminated soils. [ABSTRACT FROM AUTHOR]

The development of the first microfluidic paper-based analytical device (µPAD) for the speciation of inorganic arsenic in environmental aqueous samples as arsenite (As(III)) and arsenate (As(V)) which implements hydride generation on a paper platform is described. The newly developed µPAD has a 3D configuration and uses Au(III) chloride as the detection reagent. Sodium borohydride is used to generate arsine in the device's sample zone by reducing As(III) in the presence of hydrochloric acid or both As(III) and As(V) (total inorganic As) in the presence of sulfuric acid. Arsine then diffuses across a hydrophobic porous polytetrafluoroethylene membrane into the device's detection zone where it reduces Au(III) to Au nanoparticles. This results in a color change which can be related to the concentration of As(III) or total inorganic As (i.e., As(III) and As(V)) concentration. Under optimal conditions, the µPAD is characterized by a limit of detection of 0.43 mg L−1 for total inorganic As (As(III) + As(V)) and 0.41 mg L−1 for As(III) and a linear calibration range in both cases of 1.2–8.0 mg As L−1. The newly developed µPAD-based method was validated by applying it to groundwater and freshwater samples and comparing the results with those obtained by conventional atomic spectrometric techniques. [ABSTRACT FROM AUTHOR]

Arsenic is a toxic element with various applications. Due to the high toxicity of arsenic and its species, the determination of arsenic species in real samples is significant to control their effects on the environment and human health. A surfactant-assisted dispersive micro-solid-phase extraction was utilized as a simple and efficient sample preparation method to extract and preconcentrate arsenic (III) species in environmental, biological, and fruit samples. The microextraction method was simply combined with a chemical hydride generation strategy to determine arsenic (III) species with the graphite furnace atomic absorption spectrophotometric method. A green and magnetic sorbent was synthesized based on coating the prepared magnetic Fe3O4 nanoparticles with chitosan using a simple and straightforward chemical procedure. Usage of surfactant as a dispersion agent in the microextraction procedure enhanced the sorbent dispersion efficiency and reduced the ultrasonic time for the sorbent dispersion. Three surfactants such as sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and triton X100 were selected as representative of anionic, cationic, and neutral surfactants, respectively, and their effects were investigated in the As(III) extraction; as a result, hexadecyltrimethylammonium bromide was chosen as the best dispersion agent. Other factors that affected the microextraction method were optimized by an experimental design strategy. Under the optimum condition, a linear range was acquired in the range of 0.009–10.0 µg mL−1 with a determination coefficient of 0.9903. Limit of detection, limit of quantitation, and enrichment factor for the As(III) determination with the proposed method were 0.003 µg L−1, 0.009 µg L−1, and 21.4, respectively. The relative standard deviation (n = 5) for the As(III) determination with a concentration of 0.1 µg L−1 was equal to 3.27%. The applicability of the method for the As(III) determination was investigated by analyzing water, urine, and fruit juice samples with a relative recovery and RSD in the ranges of 94.0–97.4% and 3.17–4.54%. [ABSTRACT FROM AUTHOR]

An ultrasonic assisted slurry sampling procedure was coupled with hydride generation in-situ dielectric barrier discharge trap optical emission spectrometry (HG-in situ DBD trap-OES) to provide the simple and fast determination of arsenic in soil. The soil was treated HNO3 and HF in an ultrasonic bath for 25 min, subsequently diluted with 6% HCl (v/v) and 40 g L−1 thiourea, and placed into the ultrasonic bath again for 10 min to obtain a stable and homogeneous slurry that was introduced to HG-in-situ DBD trap-OES for As determination. Under the optimal conditions, the calibration coefficient exceeded 0.995 from 2 μg L−1 to 200 μg L−1. A method detection limit of 0.18 mg kg−1 was achieved for As in soil (250 times dilution) with a 3.4% relative standard deviation. The developed method was validated by the determination of As in three soil certified reference materials including GBW07430 (As, 18 ± 2 mg kg−1), GBW07447 (As, 10.7 ± 0.5 mg kg−1), and GBW07449 (As, 8.7 ± 0.6 mg kg−1), as well as two real soil samples. The results agreed well with the certified values and the measurements by inductively coupled plasma – mass spectrometry. With advantages of simple pretreatment procedures, small size/weight, low power consumption, and low manufacturing cost, the developed method has the potential to be widely applied in soil analysis. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Arsenic has been reported to cause damaging effects on different body organs. This study was designed to evaluate the protective effect of resveratrol (RSV) against arsenic trioxide (ATO)–induced intoxication in experimental animals. Twenty-four Wistar rats were allocated in 4 groups: group 1: control group, received normal diet; group 2: received ATO (3 mg/kg); group 3: received RSV (8 mg/kg) 30 minutes before administration of ATO; and group 4: received ascorbic acid (25 mg/kg) 30 minutes before administration of ATO. Treatments were given to experimental rats daily for consecutive 8 days. At the end of experimental period, bioaccumulation of arsenic in liver and kidney was assessed by hydride generation-atomic absorption spectrophotometer to investigate the association of arsenic accumulation with histological aberrations. Following parameters were also investigated: serum biochemical profile (alanine aminotransferase, aspartate transaminase, alkaline phosphatase, blood urea nitrogen, and creatinine) for evaluation of liver and kidney functions and lipid peroxidation and oxidative stress (malondialdehyde, glutathione, superoxide dismutase, catalase, and glutathione peroxidase) in tissue homogenates of liver and kidney for estimation of oxidative status. The findings of this study indicate that RSV remarkably ameliorated the hepatic and renal toxicity in arsenic-exposed rat model due to its strong antioxidant potential. [ABSTRACT FROM AUTHOR]

The aim of the current study was to separate and determine arsenic in water and fish samples using a novel and green solidified floating organic drop microextraction (SFODME), which is based on switchable hydrophilicity solvent (SHS)-assisted procedure followed by hydride generation atomic absorption spectrometry (HG-AAS). The 4-((2-hydroxyquinoline-7-yl)diazenyl)-N-(4-methylisoxazol-3-yl)benzene sulfonamide (HDNMBA) and tertiary amine (4-(2-aminoethyl)-N,N-dimethylbenzylamine (AADMBA) were used as ligand and SHS, respectively. The use of SHS promotes quantitative extraction of arsenic complexes into an extraction solvent (1-undecanol). Some factors that impact extraction recovery were studied. Under optimal conditions, the limit of detection (LOD) and limit of quantification (LOQ) were 0.005 μg L−1 and 0.015 μg L−1, respectively. The calibration graph was linear up to 900.0 μg L−1 arsenic, with the enrichment factor is 267. The proposed SHS-SFODME methodology for arsenic quantification in water and fish samples was successfully implemented. The environmental friendliness and safety of proposed method were approved by the Analytical Greenness Calculator (AGREE) and the Blue Applicability Grade Index (BAGI) tools. [Display omitted] • A switchable hydrophilicity solvent-assisted solidified floating organic drop microextraction (SHS-SFODME) has been proposed. • SHS-SFODME coupled to HG-AAS (SHS-SFODME-HG-AAS) for Arsenic detection. • The SHS as co-ligand and disperser solvent used. • The SHS-SFODME-HG-AAS method was successfully applied to Arseniс traces analysis. • Greenness and blueness were determined. [ABSTRACT FROM AUTHOR]

BACKGROUND The influence of the operating temperature on Hydride Generation-Atomic Fluorescence Spectrometry comes mainly from the hydride reaction and the drift of the instrument. An increase in operating temperature increases the background value of the instrument, while a low operating temperature is not conducive to hydride reaction. OBJECTIVES To investigate the effect of operating temperature on the determination of arsenic and to find the optimal temperature conditions. METHODS According to the standard method of Atomic Fluorescence Spectrometry for determination of arsenic in water, the calibration curves, the blank samples, the QC samples and the standard materials were analyzed at temperatures of 10℃, 20℃ and 30℃, respectively. RESULTS The calibration curves in three temperature conditions had good linear correlation. However, when the operating temperature increased, the blank fluorescence value and detection limit increased accordingly, and the instrument sensitivity decreased. The analytical results cannot meet the accuracy requirement. CONCLUSIONS When the arsenic content is determined by Atomic Fluorescence Spectrometry, the working temperature of the instrument should be controlled at 10-20℃, where the temperature change is relatively stable.

A simple, cost effective hydride generation atomic florescence spectrometry (HG-AFS) method was used for determination of total arsenic (As) in poultry and calf meat samples. The samples were digested in long necked glass digestion tubes using concentrated HNO3, HClO4 and H2SO4 as a mixture. The volume of acids (HNO3, HClO4) and the amount of sample to be used for digestion were optimized to achieve appropriate digestion. The accuracy of the proposed HGAFS method was tested with certified reference material (DOLT 3 Dogfish Liver, NRC, Canada) and obtained results were in good agreement with certified value. The method limit of detection (LOD) value was calculated as 0.3 ng/g and dynamic range was 25 – 5000 pg/ml. Arsenic concentrations of poultry and calf meat samples were determined accurately by using aqueous calibration standards. Totally 31 samples (calf, chicken and turkey) obtained from local markets were analyzed. It was found that the average As concentration in calf meat (12.1 ± 3.9 ng/g) was significantly higher than the poultry samples whereas the arsenic concentrations were similar in turkey (3.1 ± 1.2 ng/g) and chicken (2.8 ± 1.1 ng/g) samples. In addition, dietary intake estimation of arsenic through consumption of calf and poultry meat was calculated and according to the gathered results daily intake of arsenic via calf meat was almost two times higher than poultry meat. [ABSTRACT FROM AUTHOR]

Hydride generation (HG) coupled to cryotrapping was employed to introduce, separately and with high selectivity, four gaseous arsanes into a direct analysis in real time source for high-resolution mass spectrometry (DART-HR-MS). The arsanes, i.e., arsane (AsH3), methylarsane (CH3AsH2), dimethylarsane ((CH3)2AsH), and trimethylarsane ((CH3)3As), were formed under HG conditions that were close to those typically used for analytical purposes. Arsenic containing ion species formed during ambient ionization in the DART were examined both in the positive and negative ion modes. It was clearly demonstrated that numerous arsenic ion species originated in the DART source that did not accurately reflect their origin. Pronounced oxidation, hydride abstraction, methyl group(s) loss, and formation of oligomer ions complicate the identification of the original species in both modes of detection, leading to potential misinterpretation. Suitability of the use of the DART source for identification of arsenic species in multiphase reaction systems comprising HG is discussed. [ABSTRACT FROM AUTHOR]

In this work, we propose a colorimetric assay for the determination of trace arsenic based on in-situ formation of AuNPs with the synergistic effect of arsine (AsH 3) and iodide. AsH 3 , generated by hydride generation of AsIII in the sample or standard solution, enters into the HAuCl 4 solution containing polyvinyl alcohol (PVA) and KI, and then reacts rapidly to form AuNPs, resulting in the solution color changing from light yellow to pink. Hydride generation applied here not only produces a strong reducing agent AsH 3 , but also effectively reduces matrix interference. The introduction of I− promotes the reaction by reducing the Au precursor from trivalent state to monovalent state, thus accelerating the formation of AuNPs with AsH 3 and improving the sensitivity for the detection of arsenic. Trace AsIII as low as 10 μg L−1 in 3 mL sample solution can produce the change in color visible to the naked eye. Moreover, the use of the stabilizer PVA and the gaseous strong-reducing agent AsH 3 evenly dispersed in the reaction solution lead to the formation of well-distributed and fine AuNPs of size changing little with the dosage of AsH 3. The whole analysis process only takes 30 min under ambient condition without complicated synthesis and pretreatment. The proposed assay is simple, stable, sensitive and selective, providing a convenient and cost-effective choice for on-site trace arsenic detection in real samples. Image 1 • A simple colorimetric assay has been developed for the determination of trace AsIII based on in-situ formation of AuNPs. • Hydride generation has been applied to effectively reduce matrix interference and produce strong-reducing agent arsine. • The introduction of iodide can accelerate AuNPs forming and improve the detection sensitivity. • The assay provides a convenient and cost-effective choice for on-site determination of trace AsIII in real samples. [ABSTRACT FROM AUTHOR]

A strategy was developed for the determination of total As in birch saps (BSs) by hydride generation (HG) coupled with inductively coupled plasma optical emission spectrometry (ICP-OES). We proposed and validated a simple and robust HG-ICP-OES method with no need for tedious and long sample preparation before measurements. Corresponding As hydride was generated in reaction with NaBH4 (1.0%) in acidic conditions (10 mol L−1 HCl) after pre-reduction of As(V) to As(III) in a KI (0.5%)-ascorbic acid (2.0%)-HCl (3 mol L−1) mixture. Several different sample preparation procedures, including digestive and non-digestive approaches, were tested in order to improve the detectability of As using HG-ICP-OES. Reactivity of As towards HG under conditions of a real sample was investigated to check potential interfering effects coming from undecomposed sample matrix constituents. The proposed method included the direct analysis of untreated samples (only pre-reduction prior to HG) and precision (<6% as relative standard deviation), accuracy (94.7–108.7% as recoveries) and sensitivity (limit of detection at 0.26 ng mL−1) that was suitable for trace analysis. An absence of matrix effects allowed external calibration for quantification of As. Applicability of the method was demonstrated by determination of As in several commercially available bottled BSs. [ABSTRACT FROM AUTHOR]

The inorganic and total arsenic concentration in rice samples with different origins was determined by continuous hydride generation-atomic absorption spectrometry (HG-AAS) and inductivity coupled plasma mass spectrometry (ICP/MS). Only one sample preparation method was used for total arsenic and inorganic arsenic determination in rice samples. LOD and LOQ for HGAAS and ICPMS were 0.3, 1, and 0.003, 0.01 μg kg−1, respectively. The relative standard deviation (RSD %) of the method was in the range of 5-15 %, and 7-25 % as the relative standard deviation of 3 replicates. The validation of the method was done using CRM NIST 1568b and IGI 1385 rice flour, successfully. This method was applied for the determination of inorganic arsenic and total in 72 rice samples from five different countries of origin. The average concentration of total arsenic was 370, 269, 214, 110, and 97 μg kg−1; and inorganic arsenic was 64, 80, 92, 99, and 82 μg kg−1 in the rice samples for Argentina (AR), Uruguay (UR), United States of America (USA), Iran (IR), and India (IN), respectively. [ABSTRACT FROM AUTHOR]

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Severe changes in speciation information were observed during volatile species generation (VSG) due to de-alkylation of generated Hg species as proven by cryogenic trapping with inductively coupled plasma mass spectrometric detection (CT-ICP-MS). Methyl mercury hydride is de-methylated to Hg0 by 45% and 6%, respectively, in HCl and TRIS buffer media. Ethylmercury hydride is de-ethylated to Hg0 by 71% and 28%, respectively in HCl and TRIS buffer media. Only Hg0 as a volatile product was observed when generating from phenylmercury regardless of the reaction medium employed. These findings limit significantly the application of VSG to Hg speciation analysis, especially the possibility of generation of alkyl-substituted mercury hydrides for cryogenic trapping/separation or gas chromatography. On the contrary, post-column VSG of Hg species prior to spectrometric detection can be employed to enhance sensitivity without any negative effects on accuracy and precision of the results. Image 1 • Volatile species generation (VSG) of alkyl-substituted Hg species was optimized. • VSG for speciation analysis of Hg2+, methyl-, ethyl- and phenylmercury explored. • VSG from two reaction media, HCl and TRIS buffer, was compared. • Severe changes in speciation information found due to de-alkylation in both media. • These findings limit greatly the application of VSG to Hg speciation analysis. [ABSTRACT FROM AUTHOR]

Hydride generation (HG) was combined with an atmospheric pressure glow discharge (APGD), sustained in a completely novel system, to sensitively determine As, Sb, and Se by optical emission spectrometry (OES). The carrier gas with the analyte hydrides produced by chemical HG together with co-generated H 2 was introduced into the APGD system, where atomization and excitation processes took place. It was revealed that the essential factors responsible for the high stability of the plasma were its operating with He discharge gas (instead of Ar), operating the gas nozzle (used to introduce carrier He) as a cathode, and forcing the cathode spot to cover most of the surface of the gas nozzle. Under optimized operating conditions, the measurement repeatability was 2–3%, proving the high stability of the HG-APGD system. The detection limits (DLs) of As, Sb, and Se were 0.6, 0.14, and 1.2 μg L−1, respectively, and compared to those previously reported for HG-APGD with liquid electrodes, the DLs were improved over 3 times. In addition to improved DLs, the novel system offered a simplified and more compact design. The accuracy of HG-APGD OES was verified using a recovery test and proved by high agreement between spiked and measured concentrations of As, Sb, and Se in mineral and tap water samples, reaching recoveries within the range of 96–103%. [Display omitted] • A very simple microplasma excitation source was coupled with a hydride generation. • The operating parameters of the novel microplasma source were studied in detail. • The detection limits of As, Sb, and Se were 0.6, 0.14, and 1.2 μg L−1, respectively. [ABSTRACT FROM AUTHOR]

The resistance of three types of hydride atomizers towards interferences from other hydride forming elements and mercury was comprehensively investigated. Four hydride forming elements (Pb, Bi, Se and Te) were used as model analytes while seven hydride forming elements and mercury were investigated as potential interferents. The atomizers studied were based on a diffusion flame - DF, an externally heated quartz tube (multi)atomizer - (MM)QTA as well as a dielectric barrier discharge plasma - DBD. The performance of even two designs of DBD atomizers was compared. The first configuration (REF-SIN) was realized by a DBD chamber with glued electrodes coupled to a power supply source with sinusoidal modulation of high voltage. The second configuration of the DBD atomizer (SE-SW) comprised of a DBD chamber with the sputtered electrodes powered by a square-wave modulated high voltage source. The DF atomizer was found to be the most robust towards atomization interferences. However, its sensitivity was 30 to 50 times lower compared to (MM)QTA and DBD based atomizers due to its short optical path. The DBD atomizer in REF-SIN arrangement can compete very well with (MM)QTA atomizer in terms of resistence to interferences as well as sensitivity. The resistence of DBD atomizer in SE-SW configuration towards atomization interferences is slightly worse compared to (MM)QTA and DBD in REF-SIN design. [Display omitted] • Resistance of hydride atomizers towards atomization interferences was investigated. • Diffusion flame, quartz tube (QTA) and dielectric barrier discharge (DBD) studied. • 4 analytes and 8 potential interferents in 4 types of hydride atomizers examined. • Diffusion flame found the most robust towards atomization interferences. • DBD in REF-SIN design competes well with QTA in resistence to interferences. [ABSTRACT FROM AUTHOR]

Flow injection hydride generation atomic absorption spectrometry (FI-HGAAS) is a sensitive technique for the quantification of trace amounts of lead. However, plumbane generation is not straightforward and usually HG methods for lead are not robust enough for routine analysis. The optimum pH range for Pb HG is very narrow, so strict control of the acidity of the reaction medium is required for reliable results and in some cases even acid concentrations used for sample preservation can interfere. Moreover, some elements, like Cu, can interfere in the HG reaction suppressing the Pb signal. In this paper we report the development and validation of a method for the determination of Pb in water samples that is robust towards acidity and Cu levels usually found in water samples. All hydride generation parameters were optimized, but special emphasis was put on robustness. The use of borate as a buffer significantly improved the robustness of the method towards acidity, compared to the typical non-buffered HG. Furthermore, the interference of Cu, Sb and Sn in the HG reaction was overcome using thiocyanate as a masking agent. Other elements do not interfere at levels typically found in water samples. The limit of quantification achieved (0.9 μg L−1) is below the current guideline value for Pb in drinking water (10 μg L−1). The linearity of the method was verified between the LOQ and up to 15 μg L−1. An analytical frequency of 25 samples per hour with 3 measurement replicates each was achieved. The method was applied to the analysis of 50 water samples. The concentrations found ranged from

A novel method combining headspace single-drop microextraction with a paper-based colorimetric assay was developed. Headspace single-drop microextraction using a microdrop containing unmodified gold nanoparticles (AuNPs) as both the extractant and the colorimetric probe was used for the sensitive and selective determination of Se(IV). The method relies on the color change of the microdrop solution caused by the adsorption of in situ-generated hydrogen selenide on the surface of AuNPs. Following extraction, the microdrop was spotted onto cellulose paper, and scanometric-assisted digital image analysis was used for selenium quantification. The analytical variables affecting the method sensitivity, including the drop volume, the concentrations of KBH4, HCl, and AuNP solutions, and the extraction time, were studied. Under the optimal conditions, a linear correlation between the colorimetric signal and Se(IV) concentration in the range from 15–100 μg L−1 with a limit of quantification of 12 μg L−1 was achieved. The repeatability of the method was studied by the calculation of intraday and interday precision for the standard solutions at concentrations of 20 and 70 μg L-1. The batch-to-batch reproducibility of the AuNPs synthesized under the same conditions was also assessed. The relative standard deviations were less than 7%. The method provided satisfactory results for the determination of selenium in real samples. [ABSTRACT FROM AUTHOR]

A novel method for the determination of ultratrace Pb in seawater by solution-cathode glow discharge atomic emission spectrometry (SCGD-AES) coupled with hydride generation (HG) has been developed. In the SCGD process, the hollow Ti tube, which can introduce gas instead of a solid tungsten rod is used as a discharge anode and combined with hydride generator. HG technology can not only separate Pb from a seawater matrix and reduce the matrix interference on detection, but can also significantly improve the transfer and atomization efficiencies for SCGD-AES. The optimum working conditions for HG and SCGD-AES for quantitative analysis of Pb were determined as 1% H 2 C 2 O 4 as the masking agent and addition of 3% formic acid to increase Pb volatilization. The limit of detection (LOD) for Pb was decreased by two orders of magnitude in comparison to the SCGD-AES process alone. Under optimal conditions, the LOD for Pb was 0.17 μg L−1, and the relative standard deviation was 2.1% (n = 11) for 100 μg L−1 Pb in artificial seawater. The proposed quantification method was verified using a seawater reference material (BWQ7001-2016), and the obtained results agreed well with certified values. Finally, the approach was used to quantitatively analyse Pb in seawater, and the results agreed well with those obtained by inductively coupled plasma mass spectrometry. The recoveries of standard addition were between 96.0% and 103.0%. A novel method for determination of ultratrace Pb in seawater by solution-cathode glow discharge atomic emission spectrometry coupled with hydride generation has been developed. Image 1 • A novel method for determination of ultratrace Pb in seawater by HG-SCGD-AES. • The LOD for lead were calculated to be 0.17 μg L−1. • The method was validated by actual seawater, which agreed with ICP-MS. [ABSTRACT FROM AUTHOR]

• Rapid inorganic arsenic speciation without chromatographic technique. • Determination of iAs (III) and iAs (V) species within a single run. • On-line pre-reduction of iAs (V) occurs in less than 1 min. • Uniform sensitivity is achieved for iAs (III) and reduced iAs (V). A rapid on-line non-chromatographic hydride generation atomic fluorescence spectrometry is described and determination of inorganic arsenic (iAs (III) and iAs (V)) species is achieved within a single run. Thioglycolic acid (TGA) was used for on-line pre-reduction of iAs (V) and quantification of arsenic species was accomplished via calibration with one As form; as iAs (III). Samples and calibration standards were prepared in Tris buffer (pH:7.2) for selective hydride generation and without on-line pre-reduction, iAs (V) signal was negligible up to 150 ng ml−1. The limit of detection (LOD) values for iAs (III) and iAs (V) were 27 pg ml−1 and 36 pg ml−1 , respectively. Recovery studies were performed, certified reference material (TMDA-61) was used to test the accuracy of the method and the results were in good agreement. iAs (V) was the main form in all water samples whereas iAs (III) concentration was

Microwave-induced plasma optical emission spectrometry (MIP OES) has increasingly become a major resource for multi-elemental analysis. One of the greatest breakthroughs in the field has been the development of a commercial instrument based on a Hammer cavity, which runs on N 2 gas obtained from an air compressor and a N 2 generator. Here, we describe the most recent advances in MIP OES instrumentation, as well as related developments in sample preparation and alternative sample introduction systems, strategies to reduce the effects of background emission and analytical signal fluctuations on accuracy, and new calibration and plasma diagnostics methods. Recently published studies have contributed to minimize matrix effects and improve robustness of MIP OES analysis, which allowed for applications involving a broad range of analytes and sample types. Together, the array of recent developments in MIP OES contributes to its acceptance and increasing adoption as a cost-effective alternative in trace element analysis. Image 1 • The most recent developments in MIP OES instrumentation are discussed. • MIP OES increasingly becomes a consolidated method in trace element analysis. • MIP OES-related sample preparation and sample introduction systems are reviewed. • Plasma diagnosis and signal correction methods for improving MIP OES are discussed. • Novel calibration methods used with MIP OES for accurate analysis are reviewed. [ABSTRACT FROM AUTHOR]

A continuous flow hydride generation laser-induced fluorescence (HG-LIF) spectrometry technique has been investigated for performing trace determination of germanium (Ge). Hydride generation of Ge is performed using reagent concentrations of 2 M H3PO4 and 0.5% NaBH4 and fluorescence detection is performed using tunable dye laser radiation at 253.323 nm for Ge excitation with fluorescence measured at 303.907 nm. The HG-LIF approach provides a linear response for Ge in the concentration range from 1.0 to 50 ng mL−1 and a limit of detection of 0.1 ng mL−1. Replicate measurements at 10 ng mL−1 have a relative standard deviation of 0.1% (n = 8). Measurements of Ge in different sample matrices have demonstrated the effectiveness of thiourea and ascorbic acid as masking agents that compensate for samples containing interfering ions. The determinations of the Ge content in reference water samples, fly ash samples, and supplement capsules demonstrate that the HG-LIF approach has feasibility for measuring Ge in different sample matrices at environmentally relevant concentrations. [ABSTRACT FROM AUTHOR]

Highlights • A gas-diffusion flow analysis method for As(V) in drinking water was developed. • As(V) is preconcentrated by on-line separation using a polymer inclusion membrane. • The membrane consists of PVDF-HFP as base polymer and Aliquat 336 as extractant. • The method offers a limit of detection of 3 μg L−1. • As(V) was successfully determined in drinking water samples. Abstract The sequential application of a polymer inclusion membrane (PIM), composed of poly(vinylidenefluoride-co-hexafluoropropylene) and the anionic extractant Aliquat 336, and a microporous polytetrafluoroethylene (PTFE) gas-permeable membrane was utilized for the first time to develop a flow analysis (FA) system, for the automatic determination of trace levels of arsenate (As(V)) in drinking water as arsine. The system incorporated a flow-through extraction cell for separation and preconcentration of arsenate and a gas-diffusion cell for the separation of arsine prior to its spectrophotometric determination based on the discoloration of a potassium permanganate solution. Under optimal conditions the FA system is characterized by a limit of detection of 3.0 μg L−1 As(V) and repeatability of 1.8% (n = 5, 25 μg L−1 As(V)) and 2.8% (n = 5, 50 μg L−1 As(V)). The newly developed FA method was successfully applied to the determination of arsenate in drinking water samples in the μg L−1 concentration range. [ABSTRACT FROM AUTHOR]

A fast, sensitive, and on-line hydride generation method using ultrasonic nebulizer was applied for the determination of Sb(III) and Sb(V) by inductively coupled plasma-optical emission spectrometry (ICP-OES). In the proposed technique, an ultrasonic nebulizer was used for on-line and direct hydride generation as well as for sample introduction into the ICP-OES. The Sb(III) could be selectively determined by introducing the mixture of sample and reductant solutions directly into the ultrasonic nebulizer. The concentration of Sb(V) was calculated by the difference between total Sb and Sb(III). The effects of different experimental parameters on the performance of the method were studied. Under the optimum conditions, the limits of detection 0.04 and 0.14 ng mL−1 were obtained for Sb(III) and Sb(V), respectively. The precision of the method, evaluated as the relative standard deviation obtained by analyzing a series of ten replicates, was below 1.7% for both elements. The developed procedure was applied for the determination of antimony species in various water samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: The influence of the operating temperature on Hydride Generation - Atomic Fluorescence Spectrometry comes mainly from the hydride reaction and the drift of the instrument. An increase in operating temperature increases the background value of the instrument, while a low operating temperature is not conducive to hydride reaction. OBJECTIVES: To investigate the effect of operating temperature on the determination of arsenic and to find the optimal temperature conditions. METHODS: According to the standard method of Atomic Fluorescence Spectrometry for determination of arsenic in water, the calibration curves, the blank samples, the QC samples and the standard materials were analyzed at temperatures of 10°C , 20°C and 30°C , respectively. RESULTS: The calibration curves in three temperature conditions had good linear correlation. However, when the operating temperature increased , the blank fluorescence value and detection limit increased accordingly , and the instrument sensitivity decreased. The analytical results cannot meet the accuracy requirement. CONCLUSIONS: When the arsenic content is determined by Atomic Fluorescence Spectrometry , the working temperature of the instrument should be controlled at 10 -20°C , where the temperature change is relatively stable. [ABSTRACT FROM AUTHOR]