Editor in Chief:
Prof. Xian-Hua Li

Executive Editor:
Prof. Wei Guo

Associate Editors:
Prof. Michael Dürr
Prof. Wei Hang
Prof. Zhaochu Hu

Print ISSN:0195-5373
Online ISSN: 2708-521X
2022 SCI IF: 3.4 (JCR, Q1)

The ATOMIC SPECTROSCOPY is a peer-reviewed international journal started in 1962 by Dr. Walter Slavin. In November 2019, its ownership was transferred to Atomic Spectroscopy Press Limited (ASPL), Hongkong, P.R. China. It is intended for the rapid publication of Articles, Review/Mini-review, or Letters/Communications in the fields of elements, elemental speciation, and elemental isotopic analysis by XRF, AAS, AFS, ICP-OES, ICP-MS, GD-MS/OES, TIMS, SIMS, AMS, LIBS, AMS, NAA, INAA, various microanalysis techniques, and related sample preparation techniques. Manuscripts dealing with (i) instrumentation & fundamentals, (ii) methodology development & applications, and (iii) standard reference materials (SRMs) development can be submitted for publication.

Publishing frequency: Six issues per year

Recent Issues

Vol.44,2023,NO.4
Pages: 191-281

Full Issue

Cover

Vol.44,2023,NO.3
Pages: 119-190

Full Issue

Cover

Vol.44,2023,NO.2
Pages: 55-118

Full Issue

Cover

Vol.44,2023,NO.1
Pages: 1-54

Full Issue

Cover

Vol.43,2022,NO.6
Pages: 423-473

Full Issue

Cover

Vol.43,2022,NO.5
Pages: 364-422

Full Issue

Cover

Articles in Press
Current Issue
All Issues
Classic Articles
Virtual Issues

Carbon Isotopic Analysis of Dissolved Organic Carbon in High-Salinity Water Using a GasBench Plus coupled to an Isotope Ratio Mass Spectrometer

Jiang-yi Zhang, Wen-jing Liu*, Hui-guo Sun, Zhi-fang Xu

DOI: 10.46770/AS.2023.203

[Abstract] (0) [PDF 740.85 K] (0) [Supporting Information]

Abstract:
Analyzing the δ13C-DOC in high-salinity water remains challenging due to significant differences in interfering ions and analyte concentrations. In this study, halide interference was eliminated using an AgF solution to generate AgCl precipitate, and the δ13C-DOC was measured using a GasBench Plus preparation device coupled with isotope ratio mass spectrometry (IRMS), establishing an accurate and sensitive method to determine δ13C-DOC in high-salinity water samples. The external accuracy of the method was 0.09‰, and the difference between the measured and certified δ13C values of IAEA-601 was 0.14‰. When the carbon content of the sample was 2.0 μg (equivalent to 0.5 μg mL-1 DOC content in the sample), the precision was 0.11‰ with a 0.15‰ difference. The interference of various NaCl concentrations on the measured δ13C-DOC was evaluated, and 200 g L-1 NaCl produced an approximately -13.97‰ difference between the stable isotope result and its true value. This difference was observed when we analyzed saline samples without any measures to deal with salt interference. However, this difference was overcome using the presented procedure. The δ13C-DOC of twenty-one high-salinity water samples was determined using the proposed procedure and a total organic carbon analyzer with a high-temperature catalytic oxidation unit coupled to IRMS. The δ13C-DOC results obtained using the two methods are consistent, with differences of -0.17‰ to -0.40‰, indicating that the influence of halides is completely overcome by the proposed procedure. Therefore, the proposed method enables the analysis of the ??13C-DOC in high-salinity water regardless of the type and origin of the salt solution, provided the concentrations of DOC are between 0.5 to 50 μg mL-1, and shows great promise in allowing many labs that are currently limited to analyzing freshwaters to expand their capabilities.

Uptake and Translocation of ZnO Nanoparticles in Rice Tissues Studied by Single Particle-ICP-MS

Hao Cui, Zixuan Zhang, Tianyu Wang, Jiayi Hong, Lidan Lei, Shiqiang Wei*

DOI: 10.46770/AS.2023.202

[Abstract] (1) [PDF 2.03 M] (34) [Supporting Information]

Abstract:
Foliar spay of zinc oxide nanoparticles (ZnO-NPs) is a common practice to provide the necessary Zn element for crops, which may also be a potential source for human expose to NPs with possible adverse health effects. Presently little is known about the forms and distributions of ZnO-NPs in plants after it is applied by foliar spay due to the lack of reliable quantification method. In this work, a complexed enzymatic extractant combined with single particle-ICP-MS system (SP-ICP-MS) was developed for simultaneously determining the concentrations and size distributions of ZnO-NPs in plant tissues. The measuring conditions were optimized and the method was applied to quantify ZnO-NPs uptake and distributions in rice plants after foliar application of ZnO-NPs. The results showed that the established method could well quantify the NP concentration in plant tissues with a detection limit of 16 nm; foliar spray of ZnO-NPs increased the Zn concentration (22.66 ± 0.51 mg·kg-1) in rice grains by 447%, which was still within the limits of the food safety standard of China (NY 861-2004, 50 mg·kg-1 for Zn). ZnO-NPs larger than 60 nm cannot be directly absorbed by the leaves and may instead fall into the soil. ZnO-NPs with a size between 30-60 nm in the leaves could be retained due to the hindering effect of the cellulose-hemicellulose network. The smaller ZnO-NPs with size less than 30 nm could only be detected in stems but not in the grains, indicating that ZnO-NPs were dissociated or resolved as ionic form before they were transported into grains. The xylem and phloem were believed to be the organs responsible for the translocation and transformation of ZnO-NPs after being uptake by rice leaves. The study demonstrated the feasibility of the proposed method in characterizing NP behaviours in plants and proved the effectiveness and safety of foliar application of ZnO-NPs to rice.

Evaluation of Salt Matrix and Organic Additives in Solution Anode Glow Discharge Optical Emission Spectrometry: Taking Silver, Cadmium and Mercury as Examples

Zhaoqing Cai, Zheng Wang*

DOI: 10.46770/AS.2023.190

[Abstract] (2) [PDF 4.67 M] (39)

Abstract:
The effects of several common interfering elements, low-molecular weight organic compounds (LMWOCs), and surfactants on the analytical performance of solution anode glow discharge optical emission spectrometry (SAGD-OES) were extensively studied. The resistance to interfering elements (Na, K, Mg and Ca) of different analytes (Ag, Cd and Hg) varied wildly. At extremely low concentrations of 1 mg L-1, Ag and Cd signals were suppressed by 31-35% and 17-30%, respectively; however, even at up to 100 mg L-1 Na/K/Mg/Ca, the method exhibited satisfactory recovery rates of 91-96% for Hg measurement. These findings give references for the quantitative methods directed against different test elements. The LMW alcohols (methanol and ethanol) and carboxylic acids (formic acid, acetic acid, and propionic acid) added to solution anode exhibited complex and diverse behaviors. Signal suppression was present for Ag, while characteristic emission was enhanced in the case of Hg. Surfactants such as Triton X series gave better results in spectral pattern and analyte response, with a sensitivity increase of 1.4-3.3 times and a notable descent in background levels. Furthermore, the experimental results suggested that the Triton X-100 still improved the detection limits (DLs) and signal-to-back ratios (SBRs) of elements in samples with a certain salinity of 500 mg L-1 Na. Despite the presence of Na-rich matrix, the DLs of Ag, Cd and Hg were quite low (1.0, 0.9 and 7 μg L-1, respectively), comparable to various microdischarge spectroscopy methods and ICP-OES.

Rapid Determination of Uranium in Ore Samples by Online Extraction Coupled ICP-MS

Faliang Li, Dongfa Guo, Lili Song, Boping Li, Jiaquan Xu*, Xinglei Zhang

DOI: 10.46770/AS.2023.204

[Abstract] (2) [PDF 2.33 M] (82) [Supporting Information]

Abstract:
Rapid analysis of uranium is useful for the exploration and exploitation of uranium ore, while traditional methods always require several hours for a single analysis procedure. Herein, a novel online extraction device that incorporates a heating unit was fabricated to efficiently extract the uranium from ore, followed by real-time ICP-MS detection. As a result, without sample pretreatment, the uranium content in two kinds of uranium ore can be obtained directly within 15 min with low sample consumption (1.0 mg), low energy consumption, and high recovery (90%). The present method provided a useful platform for the rapid quantitative analysis of uranium, which is beneficial for the improvement of the efficiency of exploration and exploitation of uranium.

[Full Issue download]

[Cover download]

Article

Novel Liquid Microjunction Introduction System for Inductively Coupled Plasma Mass Spectrometry

Michael Trolio, Malek Hassan, Richard Oleschuk, Diane Beauchemin*

2023,44(4),191-197,

DOI: 10.46770/AS.2023.101

[Abstract] (51) [PDF 3.05 M] (647)

Abstract:
A novel sampling probe composed of a coaxial-tube that functions at a continuous-flow was used to inject 1 μL of sample into an inductively coupled plasma mass spectrometer. Simply touching a sample to the dome of liquid at the inlet of the liquid microjunction (LMJ) allows for sample introduction into a flowing carrier stream that transports sample into the plasma-similar to the mechanism of sample transport in flow injection analysis. This self-cleaning sampling system, allows for sampling of minute amounts of liquids at atmospheric pressure as well as leaching of soluble components off the surface of a solid. Preliminary results demonstrate the implementation of this probe in steady-state, flow injection, and surface sampling modes. A substantial reduction of matrix effects and oxide interferences resulted with 1 μL injections. In fact, the performance of LMJ with 1 μL injections in terms of spectroscopic and non-spectroscopic interference mitigation, sensitivity and detection limit is very similar to that previously reported with 1 μL mono-segmented flow analysis.

Purification of High Aluminum Content Samples for Rapid and Precise Analysis of Lithium Isotopes

Hao-Ran Duan, Zhi-Yong Zhu*, Chen-Xu Pan, Jian-Xiong Ma, Zheng-Yu Long, Kun-Feng Qiu

2023,44(4),198-206,

DOI: 10.46770/AS.2023.170

[Abstract] (18) [PDF 8.60 M] (419)

Abstract:
The analysis of lithium isotopes in high-aluminum content samples was accompanied by significant tailing of Al on Li using the traditional single-column method regardless of using single HCl or HNO3 as eluent. This hindered the precise determination of Li isotopes and made one-step column chromatographic separation of Li in silicate rocks challenging. Additional column procedures may be required to separate Li from Al in high Al samples, which would be time-consuming and result in reagent waste. In this study, the use of a 10 mL 0.2 mol L-1 HF and 0.5 mol L-1 HCl mixed eluent significantly reduced the Al tailing to less than 1% of that observed with the traditional method. The proposed purification procedure is applicable to a wide range of geological samples or minerals (e.g., silicates, seawater, sediments, and feldspars). Additionally, the matrix effect of Al and the Li concentration effect were investigated for accurate Li isotope analysis. The concentration effect, which was proved mainly led by the inappropriate treatment of the baseline. The real concentration effect yielded only a bias of 0.2‰ if normalized the solution of 20 ng g-1 Li with that of 140 ng g-1. In accounting for this, Li isotopes can now be analyzed quite accurately at variable concentrations during non-strictly concentration-matched conditions. The long-term external precision of δ7Li based on the international standard LSVEC was approximately ±0.2‰ (2SD), making it suitable for geological sample analyses. The proposed method was confirmed through the analysis of BCR-2, BHVO-2, AGV-2, BIR-1a, RGM-2, JF-1, SCo-1, GSP-2, GSR-6, and GSR-8. All the results agreed with previously published values. Besides, two in-house Li isotope solution standards CAGS-Li-P (6.25±0.25‰) and CAGS-Li-N (-15.02±0.18‰) were developed and routinely analyzed to monitor the instrumental mass bias.

Determination of Germanium Species by Hydride Generation Atomic Absorption Spectrometry: Comparison of Atomizers Based on Diffusion Flame, Heated Quartz Tube, and Dielectric Barrier Discharge Plasma

Alexandra Slota, Milan Svoboda, Vít Suchopár, Jan Kratzer*

2023,44(4),207-218,

DOI: 10.46770/AS.2023.216

[Abstract] (4) [PDF 1.43 M] (117) [Supporting Information]

Abstract:
Atomization of three volatile germanium species including germanium hydride (GeH4) and its two methyl-substituted analogues – monomethyl germanium hydride (CH3GeH3) and dimethyl germanium hydride ((CH3)2GeH2) for their detection by atomic absorption spectrometry after hydride generation was comprehensively investigated. Three types of hydride atomizers based on diffusion flame (DF), multiple microflame quartz tube atomizer (MMQTA) and dielectric barrier discharge (DBD) were optimized for atomization of Ge species. In MMQTA, the supply of air and the use of gas phase dryer are the crucial parameters affecting the sensitivity. The presence of the dryer is essential also for DBD atomizer. Sensitivity was quantified under optimized conditions reaching around 2 ms ng-1 Ge in DF and 3 ms ng-1 Ge in MMQTA atomizers, respectively. The highest sensitivity of 10 ms ng-1 Ge was observed in DBD. When compared to other hydride forming elements the sensitivity observed for Ge species is two orders of magnitude worse in MMQTA, 10-50 times lower in DBD and 5 times worse in DF. In given atomizer type, the sensitivity is comparable for all three Ge species indicating the same atomization efficiency. The fraction of Ge deposited in the DBD and MMQTA atomizers, respectively, after atomization of GeH4 was quantified to 80%. Fast decay of free Ge atoms and their deposition at the inner walls of the atomizer might explain low sensitivity observed for Ge determination by atomic absorption spectrometry. Effect of L-Cysteine (L-Cys) addition to liquid standards on response of Ge species was also investigated.

Determination of Molybdenum, Nickel, and Chromium in Low-alloy Steels Using Laser-induced Breakdown Spectroscopy Assisted with Laser-induced Fluorescence and Discrete Wavelet Transform

Nan Zhao, Zeren Luo, Jiaming Li*, Qiongxiong Ma, Liang Guo, Chun Shan, Qingmao Zhang

2023,44(4),219-226,

DOI: 10.46770/AS.2023.142

[Abstract] (21) [PDF 4.65 M] (419)

Abstract:
Molybdenum, nickel, and chromium play important roles in steel property. Laser-induced breakdown spectroscopy (LIBS) assisted with laser-induced fluorescence (LIF) is a promising technique with high sensitivity to elemental analyses. However, the spectra suffered from strong and unstable background from laser scattering when determining these three elements in steel matrix, which would deteriorate the accuracy. In this work, a self-adaptive method based on discrete wavelet transform (DWT) was introduced to solve this problem. No manual or subjective intervention is needed even if changing spectral ranges and elemental species. The LIBS-LIF spectral data were decomposed by Daubechies wavelet with the wavelet function db7 and the decomposition level 7. Then the spectra were reconstituted with background removal. In quantitative analyses, R squares in calibration curves of chromium, nickel, and molybdenum were greatly increased from 0.976, 0.965, and 0.981 to 0.995, 0.993, and 0.997, respectively; and the root-mean-square errors of cross-validation (RMSECVs) were significantly decreased from 0.0153, 0.0290, and 0.0152 wt.% to 0.00649, 0.00832, and 0.00793 wt.%, respectively. The results demonstrated both calibration model accuracy and analytical accuracy were greatly improved. This work provides an effective and convenient approach for modifying LIBS-LIF analyses in determination of molybdenum, nickel, and chromium in steels.

Nitrogen-oxygen Co-doped Magnetic Micro-carbon Adsorbent Derived from Waste Toner Coupled with GFAAS for the Analysis of Trace Lead in Environmental and Biological Samples

Jie Song, Long Qin, Yue Dong, Chenchen Zhang, Yiwei Wu, XiaoxiaoYu*

2023,44(4),227-235,

DOI: 10.46770/AS.2023.201

[Abstract] (13) [PDF 4.21 M] (566) [Supporting Information]

Abstract:
Currently, the social stock and scrappage of printers are both huge. The waste toner collected from the ink cartridges is difficult to degrade and has a small particle size, so the common treatment method is landfill, resulting in environmental pollution and resource wastage. This research aims to exploit the abundant presence of carbon black and magnetic powder in waste toner to synthesize nitrogen and oxygen co-doped magnetic carbon materials. It speculates that the amidation reaction between with the amino group of L-cysteine and the carboxylate group of waste toner in mild one-pot conditions leads to the incorporation of nitrogen and oxygen atoms. It significantly enhances the hydrophilicity of waste toner reducing the contact angle from 138.1° to 41.0° and provides active sites for the adsorption of Pb(II). Building upon this material, a novel approach combining magnetic solid-phase extraction with graphite furnace atomic absorption spectrometry has been developed for ultrasensitive lead analysis. This method demonstrates the detection limit of 43 ng L-1 with an RSD of 7.1% (CPb(II) = 0.2 μg L-1) and has been successfully employed for the analysis of trace lead in tap water, lake water, urine, and serum. Furthermore, this material exhibits rapid adsorption kinetics, robust resistance to matrix interferences, and low cost, thereby offering a novel avenue for mitigating environmental contamination through the concept of "waste-to-waste" treatment.

Numerical Simulation of Heat Conduction in Laser Ablation Based on Optimal Weight Factor

Lu-Ning Li, Zhi-Cheng Cui, Rong Shu, Jian-Yu Wang, Xue-Sen Xu, Wei-Ming Xu*

2023,44(4),236-246,

DOI: 10.46770/AS.2023.151

[Abstract] (22) [PDF 3.47 M] (394)

Abstract:
Laser ablation is a crucial process in many types of laser-matter interactions. Therefore, an accurate simulation of the laser ablation is beneficial to understanding the underlying physics in those interaction dynamics. Laser ablation simulation essentially depends on the numerical solution of heat conduction equations, usually based on finite difference strategy. Common finite difference methods include forward-Euler, backward-Euler and Crank-Nicolson schemes, corresponding to three specific finite-difference weight factors, i.e. 0, 1, and 0.5. This study proposes a new method based on an optimal weight factor, which is not a fixed value but pertinently searched for each specific problem. Taking the temporal evolution of a one-dimensional temperature field as an example, we have demonstrated that utilizing the achieved optimal weight factor can yield significantly higher accuracy than using the routine weight factors. The results in this study have the potential to better understand the heat conduction dynamics and the laser ablation physics, and hence improve the performance of relevant LMI-based techniques in the future.

Simultaneous Measurement of 147Sm/144Nd and 143Nd/144Nd Ratios in Natural Geological Samples by MC-ICP-MS After One Stage Chemical Purification Using TODGA Resin

Yueheng Yang*, Zhuyin Chu, Shitou Wu, Liewen Xie, Chao Huang, Jinhui Yang, Fuyuan Wu

2023,44(4),247-252,

DOI: 10.46770/AS.2023.169

[Abstract] (1) [PDF 769.32 K] (108)

Abstract:
We demonstrate the capability of simultaneous measurement of 147Sm/144Nd and 143Nd/144Nd ratios in natural geological samples by MC-ICP-MS after one stage chemical purification with TODGA resin as a potential alternative to the isotope dilution method. After sample digestion, one-step chemical isolation of Sm and Nd with almost 100% recovery from sample matrix elements was accomplished by using the TODGA extraction chromatography resin. The 147Sm/144Nd and 143Nd/144Nd ratios were simultaneously determined through a single analytical session utilizing MC-ICP-MS. The present analytical protocol relies on the mathematical correction of isobaric interference, thus alleviating the separation of Nd and Sm from each other and utilizing enriched tracers. The feasibility of the present protocol was investigated by the reduplicate analyses of internationally certified reference materials (CRMs), which encompassed a wide range of chemical compositions and were of a similar order as those obtained through the isotope dilution method. This also reduced the cost and time consumption of both chemical preparation and mass spectrometric measurements.

Fast Determination of Gas Evolution Volume of Calcium Carbide by Laser-induced Breakdown Spectroscopy

Yuheng Shan, Meng Wang, An Li, Xinyu Zhang, Ying Zhang, Xiaodong Liu, Ruibin Liu*

2023,44(4),253-259,

DOI: 10.46770/AS.2023.152

[Abstract] (4) [PDF 1.92 M] (169) [Supporting Information]

Abstract:
Calcium carbide is an important chemical raw material, and its gas evolution volume is a crucial indicator for its quality. However, the traditional methods to determine the gas evolution volume are costly and complicated. More important, it cannot be quantitatively detected with an in-situ real-time way. Herein, a totally new method to measure the gas evolution volume of calcium carbide based on Laser-induced breakdown spectroscopy (LIBS) is proposed for the first time. Tableting and pre-pulse were used to reduce the matrix effect. Moreover, the spectral pretreatments and standardization are necessary, including the removal of abnormal spectra, fitting and correction of background baselines and optimization of characteristic spectral line. Eventually, based on the principal component analysis combined with partial least squares method (PCA-PLS), a prediction model was successfully established, with the root mean square error of prediction set (RMSEP) of 1.498 L/kg. The average relative error of prediction set (AREP) is 0.48%. Our result illustrates that the LIBS provides a new solution for the rapid, accurate, and safe determination of gas evolution volume of calcium carbide.

The Rapid Determination of Multiple Impurities in Ultra-pure LaNi5 Alloy by Glow Discharge Mass Spectrometry

Wenhui Rong, Siwei Shi, Ling Zhang, Zhu Tao, Huogen Huang, Xinliang Zhu, Xingjian Wei*, Zhen Qin*

2023,44(4),260-266,

DOI: 10.46770/AS.2023.189

[Abstract] (1) [PDF 1.77 M] (100) [Supporting Information]

Abstract:
The chemical composition of LaNi5 needed to be measured rapidly and sensitively to control the hydrogen storage capability of the material. Glow discharge mass spectrometry (GDMS) was an excellent candidate for the measurement of LaNi5 due to its high sensitivity, simple preparation, and the capabilities of simultaneous analysis of multiple elements as well as direct analysis of solids. In practice, the application of GDMS to LaNi5 analysis was constrained by the difficulties in sample preparation arising from the morphology of LaNi5 and by the lack of the matrix-matched materials. Herein, an analytical method for the determination of 25 impurities elements in high-pure LaNi5 particles was established using GDMS. The zirconia mortar was selected as the tool for grinding the sample into powders by comparing the hardness and the introduced contaminants to those of other mortars. Under the optimized instrumental parameters, a set of relative sensitive factors (RSF) for calibration was established using nickel matrix based certified reference material, which was the analog of the matrix-matched material of LaNi5. This assumption was validated using corresponding standards with the relative error below 30% between the measured and the certified values. The previously reported universal RSFs (X. Wei, et al. Spectrochim. Acta, Part B, 2019, 154, 43–49.) were adopted for the absent elements in the available nickel standards. With this protocol, up to 25 impurity elements in LaNi5 were quantified, and the results were further validated by the other independent methods. Our work established a rapid and sensitive GDMS method for the quantitative measurement of 25 concerned impurities in LaNi5, improving the LaNi5 material analysis contents and efficiency. This method might also be applied to the sample preparation and the generation of RSFs of target element for the other complex analytes.

Review

Review: Sulfur Analysis using Inductively Coupled Plasma Mass Spectrometry

Yanbei Zhu*

2023,44(4),267-281,

DOI: 10.46770/AS.2023.187

[Abstract] (35) [PDF 1.51 M] (263)

Abstract:
This paper reviews the use of inductively coupled plasma mass spectrometry (ICP-MS) for sulfur analyses, covering articles published between January 2015 and April 2023. The ICP-MS instruments reported in the articles were classified as quadrupole ICP-MS, tandem quadrupole ICP-MS, high resolution ICP-MS, and multi-collector ICP-MS, each accounting for over 20% of the articles. Each type of ICP-MS instrument achieved detection limits < 1.0 ng/g. Laser ablation and chromatography hyphenated ICP-MS accounted for > 30% of the articles, with special attention paid to direct/imaging and speciation analyses. The leading research field in sulfur analysis is geology, followed by biology, environment, food/feed, and energy. Determination of sulfur concentrations, chemical speciation analysis of sulfur compounds, and sulfur isotope analysis accounted for approximately 30–40% of the articles. The most frequently measured sulfur isotope was 32S, followed by 34S and 33S, whereas one article reported the measurement of 36S. Selected topics of sulfur analysis using ICP-MS in research fields, hyphenated instruments, and typical applications are also introduced.

Determination of Trace Copper in Biological Samples by On-line Chemical Vapor Generation-Atomic Fluorescence Spectrometry

Liang He, Xiaofan Zhu, Li Wu, Xiandeng Hou*

, DOI: 10.46770/AS.2008.03.004

[Abstract] (205) [PDF 146.88 K] (1546)

Abstract:
On-line chemical vapor generation atomic fluorescence spectrometry (CVG-AFS) was, for the first time, used to determine trace copper in biological samples by merging acidified sample solution with potassium tetrahydroborate aqueous solution in the presence of micro-amounts of 1,10-phenanthroline. Nitric acid, for both sample digestion and chemical vapor generation, was used as the acid medium. CVG conditions and instrumental parameters were optimized for the best CVG efficiency, good gas/liquid separation, and efficient atomization/excitation. Under the optimized conditions, a limit of detection of 4 ng mL(-1) was obtained for copper, with a linear dynamic range of over three orders of magnitude. The proposed method was successfully applied to the determination of copper in biological certified reference materials.

Rapid Determination of Chemical Oxygen Demand by Flame AAS Based on Flow Injection On-line Ultrasound- assisted Digestion and Manganese Speciation Separation

Zhi-Qi Zhang*, Hong-Tao Yan, Lin Yue

, DOI: 10.46770/AS.2004.04.006

[Abstract] (207) [PDF 86.02 K] (1400)

Abstract:
A rapid, sensitive, and cost-effective method was developed for the determination of trace mercury in water samples by on-line coupling of flow injection (FI) sorption preconcentration with oxidative elution to cold vapor atomic fluorescence spectrometry (CV-AFS). race Hg(II) in aqueous solution was preconcentrated by on-line formation of mercury diethyldithiocarbamate complex (Hg-DDTC) and adsorption of the resulting neutral complex on the inner walls of a PTFE knotted reactor (KR). A mixture of 16% (v/v) HCl and 10% (v/v) H2O2 was used as the eluent to remove the adsorbed Hg-DDTC from the KR, then convert on-line the Hg-DDTC into Hg(II) prior to its reduction to elemental mercury by KBH4 for subsequent on-line CV-AFS detection. The tolerable concentrations of Cd(II) As(Ill) Se(IV) Fe(III), Co(II), Ni(II), and Cu(II) and Cu(II) for the determination of 0.1 mug L-I Hg(II) were 0.1, 10, 0.1, 0.1, 0.7, 1, 0.3, and 0.2 mg L-1, respectively. With a sample loading flow rate of 3.1 mL, min(-1) for a 60-s preconcentration, a detection limit (3sigma) of 4.4 ng L-I was achieved at a sample throughput of 36 samples h(-1). The precision (RSD, n = 11) was 1.7% at the 1 0, 1-mug L-1 Hg (11) level. The method was successfully applied to the determination of mercury in a certified reference material, GBW(E) 080392, and a number of local natural water samples.

Determination of Cadmium at the Nanogram per Liter Level in Seawater by Graphite Furnace AAS Using Cloud Point Extraction

Chun-gang Yuan, Gui-bin Jiang*, Ya-qi Cai, Bin He, Jing-fu Liu

, DOI: 10.46770/AS.2004.04.003

[Abstract] (218) [PDF 99.16 K] (1546)

Abstract:
A method based on?cloud?point?extraction?was developed to determine?cadmium?at?the?nanogram?per?liter?level?in?sea-water?by?graphite?furnace?atomic absorption spectrometry. Diethyldithiocarbamate (DDTC) was used as?the?chelating reagent to form Cd-DDTC complex; Triton X-114 was added as?the?surfactant.?The?parameters affecting sensitivity and?extraction?efficiency (i.e., pH?of?the?solution, concentration?of?DDTC and Triton X-114, equilibration temperature, and centrifugation time) were evaluated and optimized. Under?the?optimum conditions, a preconcentration factor?of?51.6 was obtained for a 20-ml, water sample.?The?detection limit was as low as 2.0 ng L-1 and?the?analytical curve was linear?in?the?10.0-200.0 ng L-1 range with satisfactory precision (RSD < 4.7%).?The?proposed method was successfully applied to?the?trace?determination?of?cadmium?in?seawater.

Development and Validation Method for the Determination of Rare Earth Impurities in High Purity Neodymium Oxide by ICP-MS

Man He, Bin Hu*, Zucheng Jiang, Yan Zeng

, DOI: 10.46770/AS.2004.01.002

[Abstract] (187) [PDF 154.90 K] (1512)

Abstract:
The analytical procedure for the determination of trace rare earth impurities in high purity neodymium oxide (Nd2O3) by ICP-MS is described. The effect of ICP-MS operating parameters on the REO(H)(+)/RE+ production ratio was studied in detail, and the optimal ICP operating conditions were established. In this context, the relationship between REO(H)(+)/RE+ production ratio and the bond strength of the rare earth oxides is also discussed briefly. For the correction of the spectral interference induced by the matrix (neodymium), a simple correction equation was used for correcting the interferences of the polyatomic ions NdO+ and NdOH+ with Tb-159 and Ho-165. The proposed method was applied to the determination of trace rare earth impurities in high purity Nd2O3\, and the analytical results were in good agreement with the recommended reference values.

Multielement Analysis of Alkaline-Resistant Glass and Basalt Glass Fibers Using Laser Ablation ICP-MS: A Useful Tool in Technical Textile Quality Control

J. Su. Becker, C. Pickhardt, N. Hoffmann, H. H?cker, J. Sa. Becker*

, DOI: 10.46770/AS.2002.01.001

[Abstract] (273) [PDF 135.56 K] (1671)

Abstract:
A powerful multielement analytical technique using laser ablation Inductively coupled plasma source mass spectrometry (LA-ICP-MS) for the sensitive determination of trace impurities in thin glass filaments, used as reinforcing material in the construction industry, was developed. The trace analysis was carried out directly on very thin solid strands (without any sample preparation steps) by LA-ICP-MS whereby a bundle of thin glass fibers (with a filament diameter of about 10 - 20 mum) was fixed on a thin, special tape of a target holder. The fibers were ablated in the ablation chamber with the aid of a commercial laser ablation system using a Nd-YAG laser at a wavelength of 266 nm). In order to verify the trace analytical data, the ablated T-glass fibers were analyzed using a quadrupole (LA-ICP-QMS) and double-focusing sector field mass spectrometer (LA-ICP-SFMS). The detection limits of the trace elements in glass fibers using the LA-ICP-MS with a quadrupole analyzer were in the sub mug g(-1) range, whereas using a sector,field mass spectrometer (LA-ICP-SFMS) the detection limits could be Improved by 3-4 orders of magnitude down to the low and sub ng g(-1) range. The multielement trace analytical method, developed for high-purity glass fibers, was applied to the determination of chemical composition on thin alkati-resistant glass and basalt fibers with finishing additives used in fine concrete for the building industry. The analytical results were quantified using standard reference materials (SRMs) of glass matrix, such as the NIST 612 glass SRM and the basalt geological reference glasses, KL-2G and ML3B-G, for the trace analysis of basalt glass fibers. The experimentally determined relative sensitivity coefficients (RSC) in LA-ICP-MS for both SRMs varied between 0.2 and 3 for most of the elements. An increase of the relative sensitivity coefficients was observed with increasing mass. The relative standard deviation (RSD) of most elements (N = 3) was T between 2 and 10%. The results of the trace element concentrations by LA-ICP-MS using different instrumentation are in good agreement.

On-line Ion Exchange Preconcentration in a Sequential Injection Lab-on-valve Microsystem Incorporating a Renewable Column With ETAAS for the Trace Level Determination of Bismuth in Urine and River Sediment

Jianhua Wang, Elo Harald Hansen*

, DOI: 10.46770/AS.2001.03.003

[Abstract] (173) [PDF 167.98 K] (1426)

Abstract:
A?sequential?injection?system?for?on-line?ion exchange separation and?preconcentration?of trace level amounts of metal ions with ensuing detection by electrothermal atomic absorption spectrometry (ETAAS) is described. Based on the use of?a?renewable microcolumn incorporated within an integrated lab-on-valve microsystem, the?column?is initially loaded with?a?defined volume of beads of an SP Sephadex C-25 cation exchange resin. After having been exposed to?a?metered amount of sample solution, the loaded bead suspension is precisely manipulated within the valve to allow reproducible elution of the retained analyte by 30 muL nitric acid (1: 16,v/v) which, via air segmentation, are then transported into the graphite tube for quantification. The content of the used?column?is afterwards discarded and new?column?material is aspirated for the next run. The ETAAS determination is performed in parallel with the?preconcentration?process of the ensuing sample. The performance of the?system?is demonstrated for the determination of bismuth. With 2.4-mL sample loading, an enrichment factor of 33.4,?a?detection limit of 27 ng 1:1, along with?a?sampling frequency of 10 h(-1) was obtained. The relative standard deviation was 2.3% for the determination of 2.0 mg 1:1 Bi (n = 7). The procedure was validated by determination of bismuth in?a?certified reference material CRM 320 (river sediment) and by bismuth spike recoveries in two human urine samples.

A Sequential Injection On-Line Column Preconcentration System for Electrothermal AAS Determination of Thallium in Geochemical Samples

Zhang-Run Xu, Shu-Kun Xu, Zhao-Lun Fang*

, DOI: 10.46770/AS.2000.01.004

[Abstract] (163) [PDF 116.38 K] (1372)

Abstract:
A?sequential?injection?system?for?on-line?sorbent extraction?preconcentration?in electrothermal atomic absorption spectroscopy was developed for the determination of trace thallium in geochemical samples. The TlBr4-1 complex was adsorbed on?a?20-mu L micro-column?(located at the tip of the furnace sampling probe) packed with XAD-8 resin. After sequentially aspirating separate zones of acetone, rinsing acid, and sample (pretreated with bromine) into?a?2.5-m long, 1-mm i.d. holding coil, the flow was reversed and directed to the?column. Sample loading, analyte adsorption,?column?rinsing and analyte elution were achieved within?a?single reversed syringe stroke. The adsorbed analyte was eluted into the furnace with 50 mu L acetone. Mutual mixing between sample, rinsing acid, and eluent were prevented by separating the zones with small air segments during metering. Tightening of?column?packing was avoided by?a?slight back-suction through the?column?after each operational cycle. With 1-mL sample loading, an enrichment factor of 15 was obtained with?a?detection limit of 18 ng/L thallium (3 sigma).?A?precision of 2.4% RSD (n=11, 4 μ g/L) and?a?sampling frequency of 11/hour were achieved. The method was applied to the analysis of geochemical samples. The results were in good agreement with the certified values of standard reference geochemical materials.

Trace Metals in Traditional Chinese Medicine: A Preliminary Study Using ICP-MS for Metal Determination and As Speciation

Xiaoru Wang, Zhixia Zhuang, Dahai Sun, Jiangxing Hong, Xihong Wu

, DOI: 10.46770/AS.1999.03.002

[Abstract] (239) [PDF 283.26 K] (1537)

Abstract:
The metal content in several TCM drugs was determined by ICP-MS. The efficiencies of different sample digestion methods were compared. Since one of the products studied is known to contain arsenic sulfides as a main ingredient, a solvent fractionation scheme was developed and applied to speciate As in the product. The metal content in the same TCM drug produced by different manufacturers was compared. The concentration of some metals such as Pb and Cd differs widely with different manufacturers, suggesting that their origin is primarily from external contamination. The high sensitivity and precision of the ICP-MS technique offers considerable advantages over conventional ICP-OES techniques for the analysis of complex samples such as TCM materials. Standardized analytic protocols based on ICP-MS are being developed fur the determination and characterization of metals and trace elements in TCM materials for product quality assessment.

Theory, design, and operation of a dynamic reaction cell for ICP-MS

Tanner S.D.* Baranov V.I.

, DOI: 10.46770/AS.1999.02.001

[Abstract] (159) [PDF 0.00 Byte] (0)

Abstract:
Theory, design, and operation of a dynamic reaction cell for ICP-MS