Multielement Trace Analysis Research Articles

Determination of trace elements in high-purity platinum by laser ablation inductively coupled plasma mass spectrometry using solution calibration

Multi-element trace analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of high-purity metals, semiconductors and insulators (e.g., ceramics) is often limited by the lack of suitable standard reference materials (SRM) with the same matrix composition and also a lack of a significant number of certified trace element concentrations in the available SRMs. This paper describes a new and easy standard-free quantification strategy using solution-based calibration for the multi-element determination of trace impurities in high-purity platinum. For the mass spectrometric measurements, a quadrupole-based LA-ICP-MS instrument was coupled with an ultrasonic nebulizer (USN). Due to the lack of a high-purity blank platinum sample, quantification of the results of LA-ICP-MS measurements was carried out using the standard additions mode in solution-based calibration. In order to achieve matrix matching, the multi-element standard solutions (with different concentrations of analytes) were nebulized successively with a USN. Simultaneously the high-purity platinum target was ablated with a focused laser beam during solution calibration with the USN. The mass spectrometric method developed was validated using a platinum standard reference material (NIST SRM 681). The analytical results of the LA-ICP-MS of SRM 681 Platinum are in good agreement with the certified values. The relative standard deviation (RSD) of most elements (n = 3) is between 2 and 10%. The proposed analysis method can be applied for other high-purity materials in a similar way, e.g., for trace and ultratrace analysis of high-purity metals, semiconductors and insulators such as high-purity ceramics.

Results of proficiency testing with regard to sediment analysis by FAAS, ICP-MS and TXRF

Three different techniques of instrumental analysis applied at ISAS were evaluated within a proficiency test, organised by IRMM in Geel. The 3 techniques, in particular flame atomic absorption spectrometry (FAAS), inductively coupled plasma mass spectrometry (ICP-MS) and total-reflection X-ray fluorescence (TXRF) were used for multielement trace analysis of a sediment sample after digestion. The reported results of up to 9 elements were evaluated with respect to the reference values after the disclosure of the latter. The relative deviations, mostly <4%, demonstrate the high accuracy of the 3 techniques. In addition, the uncertainty bars of report and reference show a high degree of overlapping, which gives evidence that the mean values are not significantly different. The high ranking of ISAS results among all 239 participants of the test confirms these findings. With regard to accuracy, ICP-MS and TXRF are somewhat inferior to conventional FAAS but in their favour they are labour- and time-saving and have a good detection power.

A new strategy of solution calibration in laser ablation inductively coupled plasma mass spectrometry for multielement trace analysis of geological samples

Because multielement trace analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is often limited by the lack of suitable reference materials with a similar matrix composition, a novel quantification strategy using solution calibration was developed. For mass spectrometric multielement determination in geological samples a quadrupole-based LA-ICP-MS is coupled with an ultrasonic nebulizer (USN). In order to arrange matrix matching the standard solutions are nebulized with a USN during solution calibration and simultaneously a blank target (e.g. lithium borate) is ablated with a focused laser beam. The homogeneous geological samples were measured using the same experimental arrangement where a 2% nitric acid is simultaneously nebulized with the USN. Homogeneous targets were prepared from inhomogeneous geological samples by powdering, homogenizing and fusing with a lithium borate mixture in a muffle furnace at 1050 degrees C. Furthermore, a homogeneous geological glass was also investigated. The quantification of analytical results was performed by external calibration using calibration curves measured on standard solutions. In order to compare two different approaches for the quantification of analytical results in LA-ICP-MS, measured concentrations in homogeneous geological targets were also corrected with relative sensitivity coefficients (RSCs) determined using one standard solution only. The analytical results of LA-ICP-MS on various geological samples are in good agreement with the reference values and the results of other trace analytical methods. The relative standard deviation (RSD) for trace element determination (N = 6) is between 2 and 10%.

Multielemental trace analysis of biological materials using double focusing inductively coupled plasma mass spectrometry detection

The analytical potential of double focusing-inductively coupled plasma-mass spectrometry (DF-ICP-MS) for total elemental analysis in clinical samples (serum, blood, urine and other biological fluids), tissues and food products is illustrated by reviewing typical applications recently published. Also, the use of DF-ICP-MS as specific detector for trace element speciation in biological samples is discussed. After adequate separation of interferences in the chromatographic column, low resolution measurements ( R = 300) can be used to provide enhanced sensitivities of more than 100 times compared with quadrupole-inductively coupled plasma-mass spectrometry (Q-ICP-MS). This capability is extremely valuable in speciation studies. Also, the use of DF-ICP-MS at low resolution could provide very precise isotope ratio measurements for isotope dilution analysis due to the ‘flat topped’ peaks obtained at this resolution. Unfortunately, the literature on these last two issues is rather scarce so far, in spite of their extremely high analytical possibilities for biological research. Moreover, the bright future of DF-ICP-MS as a most powerful multielemental detector for trace element applications in biological systems will be highlighted. Apart from applications detailed above other important application fields can be envisaged. In particular, we will speculate on its possible use to confirm/establish ‘reference values’ of trace element content in ‘normal’ populations and so to help to diagnose health and disease status, related with trace element total content or their speciation in clinical specimens.

Multi-elemental trace analysis of human serum by double-focusing ICP-MS

A method is described for the determination of a selected range of trace and ultratrace elements in human serum, using a double-focusing ICP-MS instrument (ELEMENT, Finnigan-MAT). Serum samples were diluted 1+4 with ultrapure water and addition of Sc, Ga, Y and Tl as internal standards, to a final concentration of 10 µg L –1 , was used for matrix interference correction. Low and medium resolution scans were performed on the instrument for the analyses, the first scan, at m/Δm=300, for the determination of Rb, Sr, Mo, Cd, Pb and U and the second scan, at m/Δm=3000, for the determination of those elements subject to interference at low resolution: Al, Ca, Cr, Mn, Fe, Co, Cu, Zn and Se. A SRM, 1598 Inorganic Constituents in Bovine Serum (NIST), was analysed for validation of the multi-element analysis method. Good agreement was achieved between the found levels and the certified values. The method was also applied to the multi-analysis of trace elements in serum samples from healthy subjects and from uraemic patients. Preliminary experiments carried out with both quadrupole and double-focusing ICP-MS instruments proved to be invaluable for the study of spectral and non-spectral interferences in ICP-MS detection.

Potentiometric stripping determination of heavy metals using a graphite-reinforcement carbon vibrating electrode

Potentiometric stripping determination of Cd, Cu and Zn using a vibrating electrode (VE) is presented. A simple VE was constructed by using a piezoelectric bimorph oscillator and an inexpensive graphite-reinforcement carbon (GRC) rod (a mechanical pencil). Experimental results obtained with the simple VE follow the equation valid for quantitative application of potentiometric stripping analysis (PSA) in large solutions. It was found that the GRC vibrating electrode is suitable for multielement trace analysis of small samples of 0.05 mL. The relative standard deviations for divalent metals are better than 2%.

Multi-element trace analysis by reversed-phase high-performance liquid chromatography followed by on-line column enrichment as 2-(5-nitro-2-pyridylazo)-5-[N-propyl-N-(3-sulphopropyl)amino] phenol chelates

This paper reports the utilization of 2-(5-nitro-2-pyridylazo)-5-[N-propyl-N-sulphopropyl)amino phenol (Nitro-PAPS) as a chelating reagent using an ODS column for the preconcentration and the separation of metal ions by reversed-phase high-performance liquid chromatography (RP-HPLC) with ultraviolet-visible detection of 570 nm. Nitro-PAPS chelates were eluted within 12 min with tetrahydrofuran-acetonitrile-water (15:10:75, v/v) containing a 0.01 mol dm −3 phosphate buffer solution (pH 6.0) and 2·10 −7 mol dm −3 Nitro-PAPS as the mobile phase. When the Nitro-PAPS chelates were injected into the RP-HPLC system, they were retained on top of the column and did not travel in the column, with water as the sample solvent. The retained metal chelates were then allowed to travel in the column encountering the stream of the mobile phase. The separation of the peaks to chromatogram for each component was satisfactory. The determination limits (5σ) were 0.2 ng cm −3 for copper and iron, 0.04 ng cm −3 for nickel and 0.01 ng cm −3 for cobalt. The proposed method was applied to the determination of these metal ions in actual samples, such as rain and river water.

Application of the glow discharge mass spectrometry (GDMS) for the multi-element trace and ultratrace analysis of sputtering targets

Glow discharge mass spectrometry using a VG9000 high resolution mass spectrometer has been applied to both the multi-element trace and ultra trace analyses of sputtering target materials, i.e. aluminium-based alloys, cobalt-based alloys, titanium and platinum. Element dependent relative sensitivity factors (RSF) have been determined using reference materials in order to provide the possibility for quantitative analyses. Aluminium-based and cobalt-based alloys have been extensively analysed to demonstrate precision of GDMS analyses. Detection limits in the ng/g and sub-ng/g ranges, i.e. 0.2 ng/g for U and Th have been determined in aluminium-based alloys. Comparative analyses for alloy components in cobalt-based alloys as well as trace concentrations in titanium have been performed. GDMS has been also applied to multi-element depth profile analyses in contaminated and noncontaminated platinum targets.

Comparative studies on metal determination in airborne particulates by LA-ICP-MS and furnace atomization non-thermal excitation spectrometry

Air pollution, especially by metallic aerosols, has toxic effects on soil and water, biological environment, and human health. Therefore the determination of metal contents in airborne dust is of particular relevance. For measurements with high resolution in time and space a rapid analytical method is necessary as well as short and efficient sampling. Two techniques for rapid multielement trace analysis were compared with respect to the determination of metallic, aerosol concentration in air. In both methods air was sucked through a filter material which subsequently was analyzed without any additional pretreatment. When La-ICP-MS was applied, quartz fibre filters were used as collectors which were then ablated employing a Nd:YAG laser for analyses by ICP-MS. With FANES a special porous graphite tube acted as an efficient particle collector. When inserted into the FANES source the graphite tube simultaneously serves as thermal atomizer and hollow cathode so that collected particulates were vaporized and excited in the tube for optical emission spectrometry. For signal registration an echelle polychromator was used. With FANES detection limits based on the 3 σ-criterion range between 0.2 and 2 ng/m3 for 10 elements. With quartz filters comparable results can be obtained only after enrichment by more than a 500-fold air volume. Measured metallic aerosol concentrations in ambient air by both methods do not differ within the 95% significance level.

High resolution ICP-MS ? a new concept for elemental mass spectrometry

Interfering molecular species are of major concern to the analyst currently using quadrupole based ICP-MS instrumentation. The recognized advantage and convenience offered by atmospheric plasma ionisation to multielement trace analysis can be significantly deteriorated by the limited resolving power of these analyzers. The result is poor sensitivity and lack of selectivity. With respect to sensitivity and resolution significant enhancement can be achieved by using magnetic sector based high resolution analyzers instead of quadrupoles. Unfortunately, up to now, commercially available HR-ICP-MS systems have been derived from complex instruments originally designed to meet the requirements of organic mass applications. Consequently, operation and performance of those systems expose the compromise which had to be made between an atmospheric plasma atomic ion source at high potential and an analyzer technology dedicated to molecular mass spectroscopy of organic compounds. At Finnigan MAT the first purpose designed high resolution ICP-MS has now been developed, which can be operated in high and low resolution mode at enhanced sensitivity. An innovative electric and magnetic field scanning strategy (SynchroScan) results in high on-peak duty cycles. Improved magnet technology offers high speed quadrupole style survey scans covering the full elemental mass range at nominal mass resolution. By extremely rapid peak switching, for example, all barium isotopes can be monitored in less than 100 ms with more than 90% on-peak detection efficiency. Examples are shown for computer controlled high and low resolution scan modes demonstrating the analytical performance of the new instrument concept. A comparison of detection limits achieved in low and high resolution mode is given.

New Polish certified reference materials for multielement inorganic trace analysis

An overview of the activities of the Polish Institute of Nuclear Chemistry and Technology in the field of preparation and certification of reference materials for multielement trace analysis is presented. A general strategy has been worked out and is briefly described with more detailed emphasis on the problem of data evaluation. Two geological-environmental materials recently issued [i.e. an Apatite Concentrate (CTA-AC-1) and Fine Fly Ash (CTA-FFA-1)] which were certified for 25 and 40 elements, respectively, are described. The preparation and testing of a new CRM of biological origin Oriental Tobacco Leaves (CTA-OTL-1) is presented in detail, including study of the optimum methods for drying, checking homogeneity, radiation sterilization etc. Interlaboratory comparison, in which 61 laboratories participated, yielded results enabling recommended (certified) values for 29 elements and “information values” for further 11 elements to be established.

Multielement Trace Analysis by HPLC followed by On-line Minicolumn Enrichment as Hexamethylenedithiocarbamate Chelates

Multielement Trace Analysis by HPLC followed by On-line Minicolumn Enrichment as Hexamethylenedithiocarbamate Chelates

Wide Dynamic Range Detection with a Charge Injection Device (CID) for Quantitative Plasma Emission Spectroscopy

The operation and performance of an analytical plasma emission spectrometer based on an echelle polychromator and a charge injection device (CID) two-dimensional multichannel array detector is described. Quantitative analysis methodology for measuring the intensity of emission lines over a wide dynamic range is presented. The procedure involves varying the integration time on the detector for each spectral line, based on the intensity of that line, in a process called random access integration (RAI). The factors that determine the maximum number of spectral lines that may be simultaneously observed are presented. With current CID technology these include the size of the array, the intensity of spectral lines at the focal plane, and the size of the subarrays used to record the line intensities. The sensitivity and dynamic range of the system equal those of emission spectrometers employing photomultiplier tubes, and the flexibility to use any spectral line, or group of lines, for a particular element provides unprecedented ability to perform simultaneous multielement trace analysis in complex mixtures. Background intensity in the vicinity of each spectral line is measured simultaneously, enabling precise spectral background corrections. The simultaneous availability of the information from the entire emission spectrum allows spectral features of diagnostic value such as argon, hydroxide, and carbon emission to be monitored, as well as spectral features due to the principal components of the sample matrix. Changes in analysis conditions or matrix composition can be detected because of the availability of this additional information, thereby increasing the reliability of the analytical results.

Applications of ICP-MS in marine analytical chemistry

The versatility of ICP-MS in marine analytical chemistry is illustrated with applications to the multielement trace analysis of two recently released marine reference materials, the coastal seawater CASS-2 and the non-defatted lobster hepatopancreas tissue LUTS-1, and to the determination of tributyltin and dibutyltin in the harbour sediment reference material PACS-1 by HPLC-ICP-MS. Seawater analyses were performed after separation of the trace elements either by adsorption on immobilized 8-hydroxy-quinoline or by reductive coprecipitation with iron and palladium. Simultaneous determination of seven trace elements in LUTS-1, including mercury, by isotope dilution ICP-MS, was achieved after dissolution by microwave digestion with nitric acid and hydrogen peroxide. Butyltin species in PACS-1 were separated by cation exchange HPLC of an extract of the sediment; method detection limits for tributyltin and dibutyltin in sediment samples are estimated to be 5 ng Sn/g and 12 ng Sn/g, respectively.

Evaluation of inductively coupled argon plasma mass spectrometry (ICP-MS) for simultaneous multi-element trace analysis in clinical chemistry

Download options Please wait... Article information DOI https://doi.org/10.1039/JA9880300265 Article type Paper Download Citation J. Anal. At. Spectrom., 1988,3, 265-271 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Evaluation of inductively coupled argon plasma mass spectrometry (ICP-MS) for simultaneous multi-element trace analysis in clinical chemistry T. D. B. Lyon, G. S. Fell, R. C. Hutton and A. N. Eaton, J. Anal. At. Spectrom., 1988, 3, 265 DOI: 10.1039/JA9880300265 To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Thomas D. B. Lyon Gordon S. Fell Robert C. Hutton Andrew N. Eaton

Trace element analysis by using the direct CPAA method

Multielemental trace analysis was performed at Turku Cyclotron Laboratory on purified industrial aluminium samples and Ultra-High-Purity aluminium standards, produced by VAW (FRG), by using the direct CPAA (Charged Particle Activation Analysis) method. Both types of Al were expected to contain less than 10 ppm trace element contamination. 8 to 10 MeV proton beams were used for irradiation. The absolute trace quantities were determined for some ten elements by using the cross section curves and calculating the ranges of the bombarding particles in the samples, and measuring the absolute beam current and the intensities of the characteristic gamma-lines of the activated isotopes. The investigated elements are: Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Ga, Br and Zr. The obtained results were in good agreement with the guaranteed (VAW) data.

Design criteria and sensitivity calculations for multielemental trace analysis at the NSLS x-ray microprobe

Synchrotron radiation from the National Synchrotron Light Source (NSLS) will be used for X-ray fluorescence elemental analysis at a spatial resolution of several micrometers. The initial phase in the development of the microprobe beam line will consist of obtaining a 30 μm beam spot for application to scanning X-ray fluorescence analysis. The proposed beam line will have a multilayer monochromator and an ellipsoidal mirror to provide monochromatic X-rays from 3 to 17 keV with 8:1 demagnification. Ray tracing was carried out to establish the flux of excitation photons at the target for different orientations of beam line components. These alternative layouts will be discussed in terms of optimizing experimental conditions and trace-element sensitivities. Calculated sensitivities for thin biomedical and geological matrices will be presented.

Multielemental trace analysis by proton induced X-ray fluorescence

The facility described above is the first accelerator based PIXE system installed and practically employed in Czechoslovakia. From the brief account presented here one can see that this rather unsophisticated device may be employed for solution of many analytical problems of practical importance. The device in the present experimental setup makes it possible to detect the elements with the atomic numbers above 20 at the mass level of about 10−8 g. The last value corresponds to a minimum detectable concentration of about 10−5 g/g for thin samples. Relative accuracy and precision are below 10% for the determination of the elements in the concentrations well above the detection limit. The performance of the PIXE facility will be improved substantially in the near future.

Progress in materials analysis with SIMS: Quantitative surface and interface characterization

The potential and limitations of SIMS for quantitative surface and interface characterization of technical materials are described. Quantification procedures, figures of merit and analytical strategies are discussed for surface characterization of single cristals (dopant elements in Si), homogeneous metallic thin films (multielement trace analysis), heterogeneous glass layer structures (corrosion behaviour), polycristalline metals with precipitations (C, O, Al, Si in steel) and interface analysis by depth profiling (Cr distribution in Si3N4/GaAs) as well as step scanning (segregation studies of P in W-NiFe).

Trace element analysis of waters by X-ray emission spectroscopy

X-ray emission spectroscopy is a rapid, simple and accurate method for multielement trace analysis of water. This is accomplished by trace elements precipitation with a nonspecific chelating agent APDC (ammonium-1-pyrollidine dithiocarbamate) and filtration through a Millipore filter. In that way the uniform targets suitable for X-ray analysis were made and elements in concentrations as low as few ppb could be determined. APDC chelation over broad pH ranges for different elements in seawater is discussed. The best pH range for simultaneous determination of these elements is found. Results of analysis of seawater samples taken near the island Krk in the Adriatic sea are presented.