Radionuclide detection by inductively coupled plasma mass spectrometry: A comparison of atomic and radiation detection methods

Radionuclide detection by mass spectrometric techniques offers inherent advantages over conventional radiation detection methods. Since radionuclides decay at variable rates (half-lives) and via various nuclear transformations (i.e. emission of alpha-, beta-, and/or gamma-radiation) their determination via radiation detection depends not only on decay systematics but also on detector technology. Radionuclide detection by directatom measurement, however, is dependent only on technique sensitivity and is indifferent to decay mode. Evaluation of inductively coupled plasma mass spectrometry (ICP/MS) indicates this method to be superior to conventional radiation detection techniques for many radionuclides. This work discusses factors which influence detection by both methods. Illustrative applications of ICP/MS to the ultra-trace determination of several radionuclides, including¹²⁹I, are presented.Operated for the U.S. Department of Energy by Battelle Memorial Institute under contract De-AC06-76RLO 1830.     

Determination of rare earth elements in environmental matrices by sector-field inductively coupled plasma mass spectrometry

In the framework of an international certification campaign, sector-field inductively coupled plasma mass spectrometry (sector-field ICP–MS) was used for the accurate determination of the rare earth elements in five candidate reference materials: aquatic plant, calcareous soil, mussel tissue, river sediment, and tuna muscle. All samples were taken into solution by use of microwave-assisted or mixed microwave-assisted / open beaker acid digestion. Subsequently, the samples were appropriately diluted and subjected to ICP–MS analysis. Except for Sc, all the elements involved were determined at low mass resolution (R = 300). For Sc, application of a higher resolution setting (R = 3000) was required to separate the analyte signal from those of several molecular ions which gave rise to spectral overlap at low mass resolution. Some of the heavier REE can also suffer from spectral overlap attributed to the occurrence of oxide ions (MO⁺) of the lighter REE and Ba. This spectral overlap could be successfully overcome by mathematical correction. Matrix effects were overcome by use of two carefully selected internal standards, such that external calibration could be used. On each occasion, a geological reference material was analyzed as a quality-control sample and the reliability of all results obtained was additionally checked by means of chondrite normalization. For tuna muscle the content of all REE was below the limit of detection. For calcareous soil and river sediment, low to sub μg g^–1 values were observed, whereas the REE content of aquatic plant and mussel tissue was considerably lower (low to sub ng g^–1). Overall, the results obtained were in excellent agreement with the average values, calculated on the basis of all “accepted” values, obtained in different laboratories using different techniques.     

稀土对茶叶中稀土结合糖蛋白的组成及活性的影响

应用电感偶合等离子体质谱（ＩＣＰ－ＭＳ）、气相色谱（ＧＣ）、氨基酸分析仪及动力物模型,研究了喷施稀土对茶叶中稀土结合糖蛋白（ＲＥＥ－ＴＧＰ）组成及活性的影响,成品茶中有稀土结合糖蛋白;稀土对单糖种类及组成没有明显影响,但ＲＥＥ－ＴＧＰ中羟脯氨酸（Ｈｙｐｒｏ）及丝氨酸（Ｓｅｒ）含量增加明显,而谷氨酸（Ｇｌｕ）含量则比对照区的低,稀土处理区茶叶制得的ＲＥＥ－ＴＧＰ中Ｌａ含量增加了１９３％;ＲＥＥ－ＴＧＰ具有明显的降血糖效果和增强免疫作用等活性。     

Determination of Rare Earth Elements in Garnet Minerals,Geological Materials by Inductively Coupled Plasma–Atomic Emission Spectral and Mass Spectral Analysis

Abstract

The performance of inductively coupled plasma–atomic emission spectrometry (ICP‐AES) for the determination of 14 lanthanides and Yttrium was evaluated by comparison with inductively coupled plasma–mass spectral (ICP‐MS) analysis. The geochemical reference samples (GRS), DNC‐1(diabase), AGV‐1(andesite), Sy‐2(syenite), MRG‐1(gabbro), AN‐G(anorthosite), AC‐E(granite), and MAG‐1(marine mud) were chosen as test materials and analyzed for checking the precision and reproducibility of the methods. The mineral garnet is separated from the black sands of the southwest coast of India, and the combined cation exchange–ICP method of AES analysis and MS analysis were carried out for the determination of rare earth elements. Both techniques are within the requirements needed for garnet minerals. The determination of rare‐earth elements in these minerals, which contain other elements as major contribution and trace distribution of rare‐earth elements, shows that ICP applied under the proper working condition lives up to the expectations. Major element analysis gives the formula of garnet of Manavalakurichi (MK) as (FeCaMg)_2.79Al_2.07Si_3.05O₁₂ approximated to Fe₃Al₂Si₃O₁₂, hence of almandine-type garnet. The enrichment of heavy lanthanides compared to the light lanthanides indicates that these lanthanides occupy the coordinaton site of Fe²⁺ by replacement. Both techniques are excellent in determining the very low concentration of lanthanides in geological materials, specifically garnet.     

One hundred and forty years “Fresenius’ Journal of Analytical Chemistry”

The distribution of rare earth elements (REE) in a pooled soil sample collected from Zhangzhou, Fujian Province, China, was screened by a five-step sequential extraction procedure coupled with ICP–MS determination after preconcentration of REE and removal of the matrix by extraction with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP). The results showed that the distribution of REE in the different fractions of the pooled soil sample studied followed the order soluble species (46.76%) > species bound to organic matter (22.08%) > species in the residue (16.77%) > species bound to Fe–Mn oxides (2.02%). An effective method for speciation of REE, which utilized weak cation-exchange HPLC separation hyphenated with post-column derivatization and visible or on line ICP–MS detection, was, moreover, developed and successfully applied to the speciation of REE in the soluble extract of the pooled soil sample. The stability of known complexes of lanthanum during the HPLC separation was investigated with fluoride, citrate, and ethylenediamine tetraacetic acid (EDTA) chosen as ligands modeling those in the soil. REE in the soluble extract of the pooled soil sample were subsequently classified into three types of species –≤ + 1 charged complexes (negatively charged, neutral, and +1 charged), + 2 charged complexes, and “free” REE species. This method is expected to be useful for identification of bioavailable (or toxic) species of REE in environmental samples.     

An improved method for99Tc analysis and application to human tissues

Zircon separated from samples of monazite in beach sand have been analyzed for Zr, Hf, U, Th, Sc and REE concentration by the neutron activation analysis technique. After irradiation, the rare earth elements were separated from Zr and Hf by oxalate precipitation, using La as a carrier, from²³⁹Np/U/ by ion-exchange chromatographic method and from²³³Pa/Th/ by co-precipitation with MnO₂. The chondritic normalized REE pattern of two zircon samples show negative Eu anomalies with a slope increasing at the heavy rare earths.     

端视ICP－AES系统分析性能研究──Ⅰ．在稀土分析中的应用

本工作通过比较端视与侧视ＩＣＰ的分析性能，研究了端视ＩＣＰ系统对稀土元素的分析特性。高频发生器输出功率与载气流量对端视与侧视ＩＣＰ激发特性的影响没有明显差异，取光方式的不同是二者分析性能差异的根本原因。端视ＩＣＰ由于取光时避开了产生连续背景的环形热区和截取了整个中心通道的光谱，其背景减小，谱线强度增强，获得较好的测定下限。对１４种稀土元素测定下限的比较表明：端视ＩＣＰ比铡视ＩＣＰ下降１０－３０倍。     

端视ICP-AES系统分析性能研究──Ⅰ．在稀土分析中的应用

本工作通过比较端视与侧视ICP的分析性能，研究了端视ICP系统对稀土元素的分析特性。高频发生器输出功率与载气流量对端视与侧视ICP激发特性的影响没有明显差异，取光方式的不同是二者分析性能差异的根本原因。端视ICP由于取光时避开了产生连续背景的环形热区和截取了整个中心通道的光谱．其背景减小，谱线强度增强，获得较好的测定下限。对14种稀土元素测定下限的比较表明：端视ICP比铡视ICP下降10-30倍。     

Use of chelating resins and inductively coupled plasma mass spectrometry for simultaneous determination of trace and major elements in small volumes of saline water samples

For some saline environments (e.g. deeply percolating groundwater, interstitial water in marine sediments, water sample collected after several steps of fractionation) the volume of water sample available is limited. A technique is presented which enables simultaneous determination of major and trace elements after preconcentration of only 60 mL sample on chelating resins. Chelex-100 and Chelamine were used for the preconcentration of trace elements (Cd, Cu, Pb, Zn, Sc) and rare earth elements (La, Ce, Nd, Yb) from saline water before their measurement by inductively coupled plasma mass spectrometry. Retention of the major elements (Na, Ca, Mg) by the Chelamine resin was lower than by Chelex; this enabled their direct measurement in the solution after passage through the resin column. For trace metal recoveries both resins yield the same mass balance. Only Chelex resin enabled the quantitative recovery of rare earth elements. The major elements, trace metals and rare earth elements cannot be measured after passage through one resin only. The protocol proposes the initial use of Chelamine for measurement of trace and major elements and then passage the same sample through the Chelex resin for determination of the rare earth elements. The detection limit ranged from 1 to 12 pg mL^–1. At concentrations of 1 ng mL^–1 of trace metals and REE spiked in coastal water the precision for 10 replicates was in the range of 0.3–3.4% (RSD). The accuracy of the method was demonstrated by analyzing two standard reference waters, SLRS-3 and CASS-3.     

Determination of trace metals in hydrothermal calcites by ICP-methods

Lanthanum, cerium, and europium in calcites from carbonate-sulfide banded ores were determined by standard addition using inductively coupled plasma mass spectrometry (ICP-MS). The concentration ranges in solution were for La 700-36 ng/g, Ce 2000-149 ng/g, and for Eu 140-2.4 ng/g. Only Ce was determined by both ICP methods, and the results agree within 3 to 4%. In a second step, a scan over the mass range of the rare earth elements (REE) was performed. The solutions were analyzed directly without applying preconcentration or separation procedures. ICP atomic emission spectrometry (AES) was used to determine Ca, Mn, and Fe. The matrix Ca is present in a concentration range from 1600 to 1300 g/g and the major impurities Mn and Fe are 152-32 and 100-28 g/g, respectively. The detection limits of ICP-MS for REE are found to be better by two orders of magnitude than for ICP-AES. A commercially available SCIEX Elan ICP-MS with additional software was used to make mathematical corrections for isobaric interferences and molecular ions.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

Carbon Nanofibers as Solid‐Phase Extraction Adsorbent for the Preconcentration of Trace Rare Earth Elements and Their Determination by Inductively Coupled Plasma Mass Spectrometry

Abstract

Systematic investigations were carried out into the sorption of rare earth elements (REEs) on carbon nonofibers (CNFs) by inductively coupled plasma mass spectrometry (ICP‐MS). The experimental parameters for preconcentration of REEs, such as pH, sample flow rate and volume, eluent concentration, and interfering ions on preconcentration of REEs have been examined in detail. The studied metal ions can be adsorbed quantitatively on CNFs in a pH range from 2.0 to 5.0, and then eluted completely with 0.5 mol l^?1 HNO₃. Based on the above facts, a novel method using a microcolumn packed with carbon nanofibers as an adsorption material was developed for the separation and preconcentration of REEs prior to their determination by ICP‐MS. The proposed method has been successfully applied to the determination of light (La), medium (Eu and Gd) and heavy (Yb) rare earth elements in real sample with the recovery more than 90%. In order to validate this method, two certified reference materials of tea leaves (GBW 07605) and mussel (GBW 08571) were analyzed, and the determined values are in good agreement with the certified values.     

In-situ micro-analysis of platinum and rare earths in ferromanganese crusts by laser ablation-ICP-MS (LAICPMS)

A 500 mJ Nd: YAG laser coupled to an inductively coupled plasma mass spectrometer (ICPMS) has been used for the direct determination of platinum (Pt) and the rare earth elements (REE) in concentration micro-profiles through ferromanganese crusts from the South Pacific. The instrument has been calibrated with briquetted powder pellets of U.S.G.S. reference materials NOD-A-1 and NOD-P-1. Linear calibration curves including the origin have been obtained for all elements of interest. An external calibration strategy has been developed which also accounted for variations in instrument response. The precision of the LA-ICP-MS measurements in this matrix has been 4–5% for platinum and <4% for the rare earths. Platinum concentrations have varied from 150 ng g^–1 to 500 ng g^–1 through the analysed microprofile. Two major peak areas in the platinum concentration profile have correlated roughly with cerium values and with changes in the normalised REE pattern: an enrichment of Pt coincides with a pronounced positive cerium anomaly and with an enrichment of the heavy REE relative to the light REE.     

Speciation of rare earth elements in soil by sequential extraction then HPLC coupled with visible and ICP-MS detection

The distribution of rare earth elements (REE) in a pooled soil sample collected from Zhangzhou, Fujian Province, China, was screened by a five-step sequential extraction procedure coupled with ICP–MS determination after preconcentration of REE and removal of the matrix by extraction with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP). The results showed that the distribution of REE in the different fractions of the pooled soil sample studied followed the order soluble species (46.76%) > species bound to organic matter (22.08%) > species in the residue (16.77%) > species bound to Fe–Mn oxides (2.02%). An effective method for speciation of REE, which utilized weak cation-exchange HPLC separation hyphenated with post-column derivatization and visible or on line ICP–MS detection, was, moreover, developed and successfully applied to the speciation of REE in the soluble extract of the pooled soil sample. The stability of known complexes of lanthanum during the HPLC separation was investigated with fluoride, citrate, and ethylenediamine tetraacetic acid (EDTA) chosen as ligands modeling those in the soil. REE in the soluble extract of the pooled soil sample were subsequently classified into three types of species –≤ + 1 charged complexes (negatively charged, neutral, and +1 charged), + 2 charged complexes, and “free” REE species. This method is expected to be useful for identification of bioavailable (or toxic) species of REE in environmental samples. Received: 14 November 2000 / Revised: 26 January 2001 / Accepted: 30 January 2001     

Determination of rare earth elements in tomato plants by inductively coupled plasma mass spectrometry techniques

In recent years identification of the geographical origin of food has grown more important as consumers have become interested in knowing the provenance of the food that they purchase and eat. Certification schemes and labels have thus been developed to protect consumers and genuine producers from the improper use of popular brand names or renowned geographical origins. As the tomato is one of the major components of what is considered to be the healthy Mediterranean diet, it is important to be able to determine the geographical origin of tomatoes and tomato‐based products such as tomato sauce. The aim of this work is to develop an analytical method to determine rare earth elements (RRE) for the control of the geographic origin of tomatoes. The content of REE in tomato plant samples collected from an agricultural area in Piacenza, Italy, was determined, using four different digestion procedures with and without HF. Microwave dissolution with HNO₃ + H₂O₂ proved to be the most suitable digestion procedure. Inductively coupled plasma quadrupole mass spectrometry (ICPQMS) and inductively coupled plasma sector field plasma mass spectrometry (ICPSFMS) instruments, both coupled with a desolvation system, were used to determine the REE in tomato plants in two different laboratories. A matched calibration curve method was used for the quantification of the analytes. The detection limits (MDLs) of the method ranged from 0.03 ng g^?1 for Ho, Tm, and Lu to 2 ng g^?1 for La and Ce. The precision, in terms of relative standard deviation on six replicates, was good, with values ranging, on average, from 6.0% for LREE (light rare earth elements) to 16.5% for HREE (heavy rare earth elements). These detection limits allowed the determination of the very low concentrations of REE present in tomato berries. For the concentrations of REE in tomato plants, the following trend was observed: roots > leaves > stems > berries. Copyright © 2009 John Wiley & Sons, Ltd.     

Trace rare earth element analysis of IAEA Hair (HH-1), Animal Bone (H-5) and other biological standards by radiochemical neutron activation

A radiochemical neutron activation analysis using a rare earth group separation scheme has been used to measure ultratrace levels of rare earth elements (REE) in IAEA Human Hair (HH-1), IAEA Animal Bone (H-5), NBS Bovine Liver (SRM 1577), and NBS Orchard Leaf (SRM 1571) standards. The REE concentrations in Human Hair and Animal Bone range from 10^–8 g/g to 10^–11 g/g and their chondritic normalized REE patterns show a negative Eu anomaly and follow as a smooth function of the REE ionic radii. The REE patterns for NBS Bovine Liver and Orchard Leaf are identical except that their concentrations are higher. The similarity among the REE patterns suggest that the REE do not appear to be fractionated during the intake of biological materials by animals or humans.     

冷焰ICP-MS法测定高纯稀土氧化物中铁和钙的研究

用冷焰技术对高纯稀土氧化物中Ｆｅ和Ｃａ的分析方法进行了研究。估算了测定范围和检出限,探讨了内标元素对基体影响的校正作用,测定了加标回收率,对半定量法（ＴＱ）和定量法（ＱＡ）的结果作了比较。表明冷焰条件下,痕量Ｆｅ的测定是可行的,但Ｃａ的测定结果仍不理想;ＱＡ法明显优于ＴＱ法。     

微波消解-ICP—MS法同时测定砖茶中的铅、铜、铬和16种稀土元素

采用微波消解处理样品,以电感耦合等离子质谱（ICP-MS）法同时测定砖茶中的铅、铜、铬和16种稀土元素。采用外标法绘制校准曲线,分析了茶叶国家标准物质GBW 10016,测定值与标准值吻合。检出限为0．055-0．765μg／蚝,样品测定结果的相对标准偏差为0．2％～4．7％（n=6）。用加标回收的方法评价了该方法的准确性,回收率为88．0％-102．7％。该方法测定结果与电热板湿法消解前处理测定结果相比差异不显著。     

三重四极杆电感耦合等离子体质谱(ICP-MS)法测定氧化铕中13种稀土杂质元素

稀土杂质元素直接影响高纯单金属稀土材料的整体性能,是高科技领域许多材料的重要组成部分。通过考察最佳的消解酸量、温度、时间、氧气反应气流量、稀释气流量,建立了基于三重四极杆电感耦合等离子体质谱仪(ICP-MS/MS)直接测定氧化铕中13种稀土杂质元素分析方法。该方法采用0.1%基体直接进样,可以很大程度提高前处理分析效率。利用碰撞模式测定氧化铕稀土中的Y、La、Pr、Nd、Sm、Gd、Tb、Dy、Ho、Er、Yb、Lu元素,氧气质量转移模式测定氧化铕中的Tm,两种模式结合可以有效去除多原子干扰,实现氧化铕的稳定测试分析。通过对氧化铕标准物质（GBW02902）直接测定分析,结果表明,在碰撞和氧气质量转移模式下,各元素线性相关系数（r）均大于 0.9999,方法检出限为0.001~0.023 mg/kg,测试精密度优于1.99%,13种元素的测试值都在认定值的不确定度范围之内。该分析方法操作简单,测试稳定,效率高,为实验室进行氧化铕材料中REE杂质的准确测试分析提供思路和借鉴。     

Adsorption of fission products onto soils using a fission multitracer

The adsorption behavior of fission products to various soils was studied using a multitracer. The multitracer was prepared by neutron irradiation of ²³⁵U. Distribution coefficients of fission products were obtained for seventeen kinds of Japanese soils. It was found that zirconium, niobium, and rare earth elements show high distribution coefficients for all soil samples, however, elements like alkali metals show varied values.     

Determination of uranium isotopic composition and 236U content of soil samples and hot particles using inductively coupled plasma mass spectrometry

As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The ²³⁶U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF–ICP–MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF–ICP–MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4×10^–4 and 10^–3 counts per atom were achieved for ²³⁸U in DF–ICP–QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH⁺/U⁺ was 1.2×10^–4 and 1.4×10^–4, respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 μg L^–1 NBS U-020 standard solution was 0.11% (²³⁸U/²³⁵U) and 1.4% (²³⁶U/²³⁸U) using a MicroMist nebulizer and 0.25% (²³⁵U/²³⁸U) and 1.9% (²³⁶U/²³⁸U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the ²³⁶U/²³⁸U ratio ranged from 10^–5 to 10^–3. Results obtained with ICP–MS, α- and γ-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples.