Trace element determination in thorium oxide using total reflection X-ray fluorescence spectrometry

Applicability of Total Reflection X-ray Fluorescence (TXRF) spectrometry for the determination of trace metals at concentration of µg/g level in thorium oxide was studied. The TXRF spectrometer was calibrated using a multielement standard solution and the method was validated by analyzing another multielement standard solution. Sample preparation conditions were optimized for the TXRF determinations of trace metals in thorium oxide. The elements K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Ba and Pb present in thorium oxide standards were determined after dissolving them in HNO₃/HF mixture and separating the bulk matrix, thorium, by solvent extraction using tri-n-butyl phosphate (TBP) and tri-n-octyl phosphine oxide (TOPO) as extractants. A comparison of TXRF determined concentrations of trace elements Ca, V, Cr, Mn, Fe, Ni and Cu with the certified values shows that TXRF determined concentrations have an RSD of 20% (1 s for n = 4) and are within an agreement of 20% of the certified values in most of the cases.     

微波消解-ICP-AES法测定蒙药通拉嘎-5中的多元素

采用微波消解-ICP-AES法测定了蒙药通拉嘎-5中的Fe、Cu、Cd、Ca、Mg、Mn、Zn、Sr、Co、Ni、Cr 11种金属元素的含量。结果表明,微波消解法具有快速、高效、节约试剂的优点,由于样品在高压密封系统中进行消解,避免了污染,过程易于控制,消解效率高。测定方法的回收率为98.0%~105.5%,RSD为0.6%~2.4%。蒙药通拉嘎-5中含多种金属元素,尤其Ca、Mg、Sr、Fe、Zn的含量较高。     

Direct solid atomic emission spectrometric analysis of metal samples by an argon microwave plasma torch coupled to spark ablation

Spark ablation has been combined to microwave plasma torch atomic emission spectrometry for the direct analysis of compact metallic samples. The material is ablated by a medium voltage spark (450 V, 370 Hz) in a point-to-plane configuration and swept into a 100-W, 2.45-GHz argon microwave discharge. The microwave plasma is observed end-on and the radiation analysed with a polychromator. The detection limits for Fe, Ni, Pb and Sn in brass, Cr, Cu, Ni, Mn, Mo, Si and V in steel and Cu, Fe, Mg, Mn, Si and Zn in aluminium with the microwave plasma torch in the case of measurements with a polychromator are in the μg/g range and by a factor of up to 20 higher than those obtained with spark ablation coupled to inductively coupled plasma atomic emission spectrometry using a high resolution sequential spectrometer. The stability of the emission signal depends on the element studied and relative standard deviations usually are between 0.5 and 3.5%. In the case of low-alloy steels, the linearity and the precision of the calibration could be improved by internal standardisation. Several elements (Cr, Cu, Ni, Si and V) could be determined in a steel sample (BAS SS 410/1) with high accuracy and precision.     

Application of an on-line preconcentration system in simultaneous ICP-AES

A PC-controlled on-line preconcentration system (TRACECON) developed by Knapp et al. [11], was connected to a JY-70 Plus simultaneous ICP spectrometer to preconcentrate on-line seven trace elements (Cu, Fe, Zn, Cr, Ni, Mn, V) in biological and environmental samples. EDTrA-cellulose was used as column material. The elemental concentrations were determined by simultaneous ICP-AES. The effect of pH of the sample solution on the enrichment was studied. It was found that the recoveries of chromium and iron depend strongly on the pH of the sample solution. All the elements mentioned were recovered quantitatively at pH 4.0±0.1. The flow rates of sample solution and element solution were optimized. The enrichment factors for seven elements at 5 ml loading volume range from 3.9 for Cu to 7.9 for Zn. The detection limits of all seven elements were improved. The accuracy of the method was tested by the analysis of a number of CRMs of NIST, BCR and NIES. Most results are in good agreement with the certified values.On leave from Shanghai Institute of Metallurgy, Academia Sinica, Shanghai 200050, People's Republic of China     

抗癌草药半边旗微量元素含量的分析

用等离子体发射光谱法测定了广州和化州两地区半边旗的２５种元素，在检出的２０种元素中，含有人体必需的微量元素Ｆｅ、Ｚｎ、Ｃｕ、Ｍｎ、Ｃｏ、Ｍｏ、Ｎｉ、Ｃｒ、Ｖ，以Ｚｎ、Ｍｎ、Ｆｅ、Ｃｕ等元素含量较高，这为研究微量元素对半边旗的生长和抗癌作用的影响提供了启示。     

高效液相色谱光度法测定痕量铜、锌、铁、锰的磺化四苯基卟啉配合物

本文用磺化四苯基卟啉作柱前衍生试剂,研究了试剂与铜(Ⅱ)、锌(Ⅱ)、铁(Ⅲ)及锰(Ⅱ)的络合反应。在ODS柱上,用乙腈-水(40:60,V/V)作流动相,溴化四丁基铵作离子对试剂,在420nm波长处进行光度检测。提出了离子对反相高效液相色谱快速分离及测定痕量铜、锌、铁及锰的新方法。检测下限为(×10^-3ppm):Mn 3.6、Fe 1.8 、Zn 0.93、Cu 0.70。应用于植物样品中痕量铜、锌、铁及锰的测定,分析结果与标准参考值相符。     

Experiences with a commercial computer-controlled monochromator for use with an ICP source

The possibilities provided by a commercial computer-controlled monochromator JY-38 P have been investigated in the ICP analysis of a number of elements. Detection limits of Be, Cr, Cu, Mn, Ni, Pb, Sr and Zn after optimization for highest SBR and lowest matrix effect are given. The accuracy is assessed by analysing XRF multielement standards in measurement modes with and without background correction.     

微波消解/ICP-OES法同时测定发菜中Fe、Cu、Mn、Zn

采用微波消解处理样品,电感耦合等离子体发射光谱(ICP-OES)测定了发菜中微量元素Fe、Cu、Mn、Zn含量。结果表明,各元素检出限分别为1.58、0.79、0.52、0.67μg.mL1;相对标准偏差均小于2.2%;回收率为92.7%~101.3%。该法精密度高、准确度好,所测数据可为发菜的合理利用提供依据。     

Flow injection flame atomic absorption determination of Cu, Mn and Zn partitioning in seawater by on-line room temperature sonolysis and minicolumn chelating resin methodology

A flow-injection system is developed for Cu, Mn and Zn partitioning in seawater by flame atomic absorption spectrometry. The first approach is where the trace metal species are fractionated in situ, but analysis is performed by using a flow injection manifold in the laboratory. This operational mode is used for the determination of the dissolved labile metallic fraction and is based on the elution of this fraction from a minicolumn packed with a chelating resin containing iminodiacetic acid groups (Serdolit Chelite Che) loaded in situ with the sample. The second is used for the determination of total dissolved concentrations of trace metals. This last mode is based on the retention/preconcentration of total dissolved metals on the chelating resin after on-line sonolysis of seawater samples acidified with diluted nitric acid to breakdown the metal-organic matter complexes. The figures of merit for Cu, Mn and Zn determinations in both fractions are given and the obtained values are discussed. The fractionation scheme is applied to the analysis of coastal seawater samples collected in Galicia (Northwest, Spain). The results of fractionation showed that Mn and Zn are mainly in the labile fraction, while Cu was mainly present in the organic fraction.     

Optimization of atomic fluorescence measurements with a microcomputer-based time-multiplex multiple-slit spectrometer

An automated multielement flame atomic fluorescence (AF) spectrometer is described. The instrument employs a multiple exit slit monochromator and a single detector. Each element is excited to fluoresce with a single-element hollow cathode lamp (HCL) and a time-multiplex mode is used for pulsing the HCLs and gated data acquisition. A microcomputer controls the pulsing of HCLs, sample introduction into the flame and data acquisition. Optimization of the HCL pulse width and peak current is shown to be critical. With an air/H(2) flame sheathed with Ar, the following single-element detection limits (in mug/ml) were obtained: Au, 0.2; Cd, 0.005; Co, 0.03; Cu, 0.003; Fe, 0.05; Mg, 0.0008; Mn, 0.007; Ni, 0.04; Pb, 1 and Zn, 0.02. Some multielement detection limits were a factor of 2-5 worse. At higher analyte concentrations, the signal to noise ratio decreased due to an increase in the relative analyte fluorescence flicker noise.     

Determination of trace elements in uranium oxide by Total Reflection X-ray Fluorescence spectrometry

A study on the applicability of Total Reflection X-ray Fluorescence for the determination of multielements in trace amounts in U₃O₈ matrix has been made. The calibration of the Total Reflection X-ray Fluorescence spectrometer and the validation of the method were done using multielement standards. The trace elements present in U₃O₈ standards and samples were determined after separating the U matrix by solvent extraction using tri-n-butyl phosphate and trioctyl phosphine oxide as extractants. From the aqueous phase the elements K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Rb, Sr, Y, Zr, Pb and Ba, etc., were determined by Total Reflection X-ray Fluorescence using Ga as an internal standard. An intercomparison of the Total Reflection X-ray Fluorescence determined concentrations of the trace elements specific to nuclear fuel, e.g. Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn in U₃O₈ standards/samples with certified concentrations for these elements in U₃O₈ standards and Inductively Coupled Plasma Atomic Emission Spectroscopy determined concentrations in real U₃O₈ samples was also made. The method shows a precision and accuracy better than 5% (1σ) for most elements in concentration range of ng/mL with a sample size of 10 μL.     

Transport efficiencies and analytical determinations with electrothermal vaporization employing electrostatic precipitation and electrothermal atomic spectroscopy

Analyte transport efficiencies of solid as well as liquid samples were determined for electrothermal vaporization (ETV). A graphite furnace of the boat-in-tube type was employed for ETV. The generated aerosol was transported by an argon flow via a tubing into an external precipitator and deposited on a L’vov platform with a corona-like discharge. The sample on the secondary platform was analysed with a laboratory-constructed coherent forward scattering multielement spectrometer. For determining the analyte transport efficiencies, the comparative measurements were carried out with standard solutions dosed directly on the platform in the spectrometer furnace. The simultaneously investigated elements were Cu, Fe and Mn in the standard reference material BCR CRM 189 wholemeal flour and in a multielement standard solution containing approximately the same element ratio as certified for the solid sample. ETV boat-to-L’vov platform transport efficiencies of approximately 19% for Cu, 24% for Fe and 19% for Mn were calculated for both solid samples and multielement standard solutions. Cu, Fe and Mn in wholemeal flour were determined simultaneously by calibrating against aqueous multielement standard solutions injected into the boat as well as by the standard addition method. The results agree satisfactorily, the deviations from the certified values are below 10% and the relative standard deviations are typically 5–8%. The limits of detection are 250 pg for Cu (λ=324.8 nm), 230 pg for Fe (λ=248.3 nm) and 90 pg for Mn (λ=279.8 nm), loaded into the ETV boat.     

On-line preconcentration and ICP determination for trace metal analysis

The use of a closed-loop on-line enrichment procedure in combination with an ICP plasma emission spectrometer has been developed for the analysis of trace metal ions, such as Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. The procedure utilizes a preconcentration column filled with an anion exchange resin and 8-hydroxy-7-iodoquinoline-5-sulphonic acid is added to the sample prior to preconcentration. Details on the optimization of pretreatment and instrumental conditions are described. Results obtained for the analysis of river water and antarctic seawater are reported.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

Use and limitations of ICP-OES in wine analysis

At present, some 50 inorganic components in wine can be detected, of which 8 are mineral matter at concentrations down to 1 mg/l, about 25 are trace elements with concentrations of 0.001–0.1 mg/l, and about 20 are ultratrace elements at concentrations below 1 g/1. It has been shown that ICP-OES, a typical multielement detection method, permits the fast and reliable simultaneous determination of whole range of these inorganic species in wine, and thus can help in solving practical problems in wine manufacture. For instance, the metal content of wine can be checked, and corrosion and contamination monitored. Ten trace elements (Al, Cd, Co, Cr, Cu, Fe, Mn, Pb, V, Zn) which may be toxic or to which wine is sensitive, can be determined, and their decrease through fermentation and fining established. Above all, ICP-OES seems suitable for defining the grape type and origin of wines in wine taxonomy (pattern analysis). Data obtained by ICP-OES can also help in assigning a vintage year.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria     

信宜市教育城幼儿园幼儿微量元素营养评估及分析

为了对信宜市教育城幼儿园幼儿微量元素营养进行评估,共采集了教育城幼儿园幼儿239例头发,其中男165例,女74例,用电感耦合等离子体发射光谱法测定头发中的钙、锌、铁、铜、锰和铅的含量,其结果分别为：钙584．844-178．76μg/g,锌178．10±83．38μg/g,铁61．67±17．49μg／g,铜14．03±8．92μg／g,锰2．86±1．73μg／g,铅7．13±2．83μg／g。按照世界卫生组织的四级评估标准进行评估,钙、锌和锰等元素没有发现中度以上的营养缺乏现象,其中铁只有0．4％重度营养缺乏,铜只有8．0％中度营养缺乏,有害元素铅没有发现中度以上超标现象。比对结果,信宜市教育城幼儿园幼儿微量元素营养水平,远优于当地及周边城市的幼儿园幼儿。幼儿园幼儿微量元素营养是否均衡,应作为幼儿园总体评估指标之一。     

Analytical investigations of tree rings by laser ablation ICP-MS

Laser sampling inductively coupled plasma mass spectrometry has been used for the quantitative determination of trace elements to characterize annual growth rings of trees. The elements studied are Mg, Al, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd, Ba, Tl, Pb, Bi and U. Cellulose mixed with multielement standard solution pressed into pellets were used for the calibration. Using internal standardization with ¹²C the precision is typically better than 10% relative standard deviation. The limits of detection were limited by the purity of the cellulose. Analytical figures of merit and the analytical results are discussed in terms of environmental analysis.     

Regional distribution of manganese,iron, copper,and zinc in the rat brain during development

Manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn) concentrations were determined in the brain regions of normal 1-, 3-, 5-, 7-, 14-, 21-, 42-, 77-, and 147-day-old Wistar rats using inductively coupled plasma mass spectrometry (ICP-MS), and their maps were illustrated in color to visually compare the distribution of the elements at various stages of the growth process. Sagittal slices (1-mm thickness) sectioned at the level of the substantia nigra were divided into 18 regions, and the small slice samples were digested in microwave-assisted closed vessels for ICP-MS measurement. Mn, Fe, Cu, and Zn concentrations increased region-specifically with age, and their distributional maps showed some characteristics. These findings are discussed in terms of needs for these trace elements in the normal brain. Among new findings about their brain distribution, it is especially noteworthy that higher concentrations of Mn, Fe, and Zn were observed in the substantia nigra compared with those in neighboring regions. The mapping method in this work is expected to open up possibilities for screening of the in vivo element–element interrelationships among these essential elements.     

Multielement trace determinations in A12O3 ceramic powders by inductively coupled plasma mass spectrometry with special reference to on-line trace preconcentration

The use of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of trace elements in Al₂O₃ powders is reported. Special interest is given to a preconcentration of the trace elements by on-line coupling of chromatography to ICP-MS. This is based on the complexation of Co, Cu, Cr, Fe, Ga, Mn, Ni, V and Zn with hexamethylene-dithiocarbamate (HMDC), their preconcentration on a C18 RP column by reversed phase liquid chromatography and their elution with CH₃OH-H₂O mixtures. A direct coupling of the HPLC system to the ICP-MS has been realized by high pressure pneumatic nebulization using desolvation. With the Chromatographie method developed, removal of the AI by at least 99% was achieved. For the trace elements V, Fe, Ni, Co, Cu and Ga, high and reproducible recoveries (ranging from 96–99%) were reached. The method developed has been shown to considerably enhance the power of detection as compared with direct procedures, namely down to 0.02–0.16 ( for V and Fe, respectively. The possibilities of the method are shown by the determinations of V, Mn, Fe, Ni, Co, Cu, Zn and Ga at the μg/g level in A1₂O₃ powders. The accuracy of the method at the 0.06 to 9.0 level for Co and Fe, respectively, is demonstrated by a comparison with results of independent methods from the literature.     

Trace element analysis of human blood serum by neutron activation analysis

An attempt was made to see if there is any correlation between the trace element concentrations in the human blood serum and some specific disease. The serum samples of the patients suffering from cancer, Down syndrome, and Banti syndrome were analyzed by the neutron activation method and compared with the trace element concentrations observed among the clinically healthy men. The cancer patients gave below normal concentrations in Rb, Mn, Fe, Co, Cu, Zn, Al and Se. The Down syndrome patients were found to have similar deficiencies in Cr, Mn, Fe, Co, Zn, Cu and Sb.     

色谱分离ICP-AES法测定高纯度八氧化三铀中的13种微量杂质

采用磷酸三丁酯（TBP）萃淋树脂色层分离铀，用电感耦合等离子体-原子发射光谱法测定分离后的离纯度铀氧化物的杂质元素Al、Ca、Cr、Cu、Fu、Mn、Mo、Ni、P、Ti、V、Zn、Zr，除Al、Fe、Mo外的其余10种元素的测定结果符合标准物质定值的要求。