DOCSLIB.ORG

ICP-OES, ICP-MS and AAS Techniques Compared

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
ICP-OES, ICP-MS and AAS Techniques Compared ICP OPTICAL EMISSION SPECTROSCOPY TECHNICAL NOTE 05 ICP-OES, ICP-MS and AAS Techniques Compared Geoff Tyler Jobin Yvon S.A.S, Horiba Group Longjumeau, France Keywords: atomic spectroscopy, detection limit, linear dynamic range, interferences, precision, cost of ownership, sample throughput 1 Introduction Inductively coupled plasma-optical emission 7. What sample volume is typically available? spectrometry (ICP-OES) is an attractive tech- 8. What other options/accessories are being nique that has led many analysts to ask whether considered? Why? 9. How important is isotope information to it is wiser to buy an ICP-OES or to stay with their you? trusted atomic absorption technique (AAS) (1). 10. How much money is available to purchase or More recently, a new and more expensive tech- lease? nique, inductively coupled plasma-mass spec- 11. What is the cost of ownership and running trometry (ICP-MS), has been introduced as a rou- costs for the techniques to fulfill the require tine tool (2). ments? 12. What level of skill operator is available to you? ICP-MS offers initially, albeit at higher cost, the advantages of ICP-OES and the detection limit advantages of graphite furnace-atomic absorp- For many people with an ICP-OES background, tion spectrometry (GF-AAS). Unlike the famous ICP-MS is a plasma with a mass spectrometer as prediction by Fassel, "…that AAS would be dead a detector. Mass spectroscopists would prefer to by year 2000….", low cost flame AAS will describe ICP-MS as mass spectrometry with a always have a future for the small lab with sim- plasma source. Either way, the technique is capa- ple needs. ble of giving isotope information. This informa- tion can help to overcome many of the "spectral" This article will briefly describe these three tech- interference problems that can occur in the mass niques, and point out the important criteria by spectrometer. which to judge their applicability to your own analytical problems. Table 1 below shows a Basically, the sample introduction system and checklist of common analytical requirements and plasma of ICP-OES and ICP-MS look similar. In may help in the assessment of the techniques. ICP-OES, the optical spectrum with a typical range of 165-800nm is viewed and measured, either sequentially or simultaneously. The simul- taneous ICP-OES can be faster for a large num- Table 1: Checklist of analytical requirements bers of elements, but more expensive, than 1. How many samples/week? sequential ICP-OES. This greatly depends on the 2. What are the sample types? (Steels, rocks, number of elements, and the concentrations effluents, soils, etc) required. More recently several ICP-OES spec- 3. What method of dissolution may be trometers are able to reach to 120 nm (3), thus employed? enabling the determination of Cl at the primary 4. How many and what elements need to be wavelength of 134.664 nm with sub-ppm detec- determined? tion limits. 5. Is Chlorine important (far UV option for some ICP-OES spectrometers)? ICP-MS extracts the ions produced in the plasma 6. What are the concentration ranges? into an interface consisting of a sampler cone fol ICP OPTICAL EMISSION SPECTROSCOPY TECHNICAL NOTE 05 lowed by a skimmer cone. This configuration m/z, in the mass region 3-250 Dalton. The isotope enables the pressure to be reduced differentially information can be used in several ways; these from atmospheric pressure down to a final pressure include isotope ratio measurements, often used for of between 10-5 to 10-7 Torr. The ions, once through Pb and U that do not have a constant natural abun- the interface, are passed through ion optics, which dance, and analysis of samples having unnatural optimize the ion paths to eliminate neutral species isotope abundances. and light, usually by a photon stop. The ions then pass through a mass filter, usually a quadrupole, Isotope dilution is a method of spiking the samples before the selected ions reach the detector. with a known concentration of a pure isotope to obtain a very accurate determination of the con- The ICP-MS provides information for each atomic centration of the element. A prerequisite of this mass unit (amu), or Dalton. The ratio of the mass technique is that the element of interest must have of the ion to its charge, is displayed, and labeled more than one isotope. Figure 1: Typical quadrupole ICP-MS Figure 2: Typical sequential (monochromator) ICP-OES 2 ICP OPTICAL EMISSION SPECTROSCOPY TECHNICAL NOTE 05 Figure 3: Typical double beam AAS 2 Detection limits ICP-MS detection limits are very impressive (Table The far UV capability of some ICP-OES spectrome 3, page 10). Most detection limits are in the 1-10 ters has opened up some new applications, notably part per trillion (ppt) range for solutions. These are Cl in oils. Modern ICP-MS spectrometers have now as good as, or better than, GF-AAS for most ele- eliminated negative ion capability to reduce the cost ments in pure water and also cover many more ele- of manufacture. This has left these ICP-OES spec- ments. ICP-OES has typically two to three orders of trometers as the only atomic spectroscopy method magnitude poorer detection limits than ICP-MS, for the determination of Cl, Br, and I. with most elements in the 1-10 part per billion (ppb) range. Flame AAS has generally poorer detection limits than ICP-OES except for the alkalis metals, e.g., Na, K. Recently, one ICP-OES spectrometer (11) has shown impressive detection limits in the sub-ppb region for some elements using a high-resolution 3 Types of interferences monochromator with a radially viewed plasma. Other spectrometers have been able to get improve- The three techniques exhibit different types and ments using an axially viewed ICP, although this complexity of interference problems. For this rea- view has problematic matrix interferences. son, we will look at each technique separately. It should be noted, however, that the comment above about ICP-MS detection limits is for simple 3.1 ICP-MS Interferences solutions having low levels of other dissolved mate- rial. For detection limits related to concentrations in 3.1.1 Spectral the solid, the advantage for ICP-MS can be degrad- ed by up to 50 times because of the poorer dis- solved solids capability. Some common lighter ele- The spectral interferences in ICP-MS are predictable ments (e.g., S, Ca, Fe, K and Se) have serious inter- and number less than 300. Polyatomic and isobaric ferences in ICP-MS, which degrade the detection interferences are found where a species has a sim- limits considerably. ilar mass to the analyte, whereby the resolution of the spectrometer (generally around 0.8 Dalton) will not resolve it, e.g. 58Ni on 58Fe, 40Ar on 40Ca, 3 ICP OPTICAL EMISSION SPECTROSCOPY TECHNICAL NOTE 05 40Ar16O on 56Fe, or 40Ar-40Ar on 80Se. Element equations (similar in principle to inter-ele- Solutions for ICP-MS analysis are normally prepared ment correction in ICP-OES) can be used. In many in nitric acid however care is sometimes required cases alternative isotopes with lower natural abun- (Table 4, page 10). dances may be employed. The use of mixed gases (small percentages of other gases such as nitrogen 3.1.3 Doubly charged ions or ammonia added to the main argon gas) can sometimes be effective in reducing interferences. Any doubly charged ions will cause a spectral inter- ference at half the m/z of the singly charged ions, More recently collision cell technology has offered e.g., 138Ba++ on 69Ga+ or 208Pb++ on 104Ru+. the ICP-MS spectroscopists the opportunity to measure low concentrations using these optimal These interferences are few and can be consider- masses. However, comments within the industry ably minimized or effectively eliminated by optimiz- still pose caution on its applicability with routine ing the system before proceeding with the analysis. analysis. Optimal gas choice is still problematic especially for a routine busy laboratory. 3.1.4 Matrix effects The background in ICP-MS is so low, typically <10 counts/second, that it doesn't pose a problem. This Transport effects include spray chamber effects is a major reason for the superior detection limits of ("adaptation” effect) and differences in viscosity ICP-MS. between sample solutions and calibration stan- dards. This will change the efficiency of aerosol production from one solution to another. Matrix 3.1.2 Matrix acids matching is usually required, although internal stan- dardization can be used as an alternative method. It should be especially noted that HCl, HClO , The rapid scanning speed of ICP-MS does give 4 superior results when using an internal standard. H3PO4 and H2SO4 may cause considerable spectral problems. Polyatomic interferences are caused by Cl+, P+, S+ ions in conjunction with other matrix elements like Ar+, O+, H+. Examples are: 3.1.5 Ionization 35Cl40Ar on 75As and 35Cl16O on 51V. Ionization effects can be caused by samples con- The avoidance of HCl, HClO4, H3PO4 and H2SO4 in taining high concentrations of Group I and II ele- ICP-MS is paramount (Table 5, page 11) for most ments. Matrix matching, sample dilution, standard analyses. Where this is not possible, separation addition, isotope dilution, extraction or separation chromatography (micro-columns) may be used by chromatography may be necessary. Ionization before the sample is introduced into the plasma. buffers cannot be used due to the dissolved solids. Many favor this method to get rid of the unwanted species and it also creates an opportunity to pre- concentrate at the same time. Other techniques 3.1.6 Space charge effects used to overcome these problems are: electro-ther- mal vaporization (ETV) and mixed gases.
Load more

Recommended publications
  • Chapter 3 the Measurement Technique of Isotope Dilution
    Chapter 3 The measurement technique of isotope dilution inductively coupled plasma mass spectrometry (ICP- MS) 3.1 Introduction Total metal analysis, including trace and ultra trace elemental analysis of geological materials, have traditionally been performed using analysis methods such as atomic absorption spectroscopy (AAS), X-ray fluorescence (XRF), instrumental neutron activation analysis (INAA)[22]. Other methods include flame emission spectrometry, spectrophotometric analysis, ion selective electrode potentiometry, UV/VIS spectroscopy, candoluminescence, etc[10, 11]. Over the past 30 years more versatile measurement techniques have been developed in the form of inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). The first requirement for this study was to re-certify SARM 1 to 6 using a definitive technique with the potential to be a primary reference measurement procedure (primary method) as defined in Chapter 1[2]. Firstly, the method must be performed at the highest level of accuracy (trueness and precision)[2, 23]. Secondly, a complete measurement model must be defined in terms of SI units to facilitate the complete evaluation of all contributions to the measurement uncertainty in accordance with the Guide to the Expression of Uncertainty of Measurement (ISO GUM)[4]. Isotope dilution mass spectrometry is a direct ratio method which has been identified by the Consultative Committee for Amount of Substance (CCQM) of the International Committee for Weights and Measures (CIPM) to have the potential to be a primary method [1]. Isotope dilution measurements can be made with inductively coupled plasma mass spectrometry (ICP-MS), which is specifically suited to trace and ultra trace elemental analysis of geological materials.
    [Show full text]
  • Calibration Graphs in Isotope Dilution Mass Spectrometry Pagliano, Enea; Mester, Zoltán; Meija, Juris
    NRC Publications Archive Archives des publications du CNRC Calibration graphs in isotope dilution mass spectrometry Pagliano, Enea; Mester, Zoltán; Meija, Juris This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur. For the publisher’s version, please access the DOI link below./ Pour consulter la version de l’éditeur, utilisez le lien DOI ci-dessous. Publisher’s version / Version de l'éditeur: https://doi.org/10.1016/j.aca.2015.09.020 Analytica Chimica Acta, 896, pp. 63-67, 2015-10-08 NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=c963874f-036a-4da0-9def-eead416e46d9 https://publications-cnrc.canada.ca/fra/voir/objet/?id=c963874f-036a-4da0-9def-eead416e46d9 Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB. Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information.
    [Show full text]
  • Calorimetry Has Been Routinely Used at US and European Facilities For
    10. PRINCIPLES AND APPLICATIONS OF CALORIMETRIC ASSAY D. S. Bracken, and C. R. Rudy I. Introduction Calorimetry is the quantitative measurement of heat. Applications of calorimetry include measurements of the specific heats of elements and compounds, phase-change enthalpies, and the rate of heat generation from radionuclides. The most successful radiometric calorimeter designs fit the general category of heat-flow calorimeters. Calorimetry is used as a nondestructive assay (NDA) technique for determining the power output of heat-producing nuclear materials. The heat is generated by the decay of radioactive isotopes within the item. Because the heat-measurement result is completely independent of material and matrix type, it can be used on any material form or item matrix. Heat-flow calorimeters have been used to measure thermal powers from 0.5 mW (0.2 g low-burnup plutonium equivalent) to 1,000 W for items ranging in size from less than 2.54 cm to 60 cm in diameter and up to 100 cm in length. Calorimetric assay is the determination of the mass of radioactive material through the combined measurement of its thermal power by calorimetry and its isotopic composition by gamma-ray spectroscopy or mass spectroscopy. Calorimetric assay has been routinely used at U.S. and European facilities for plutonium process measurements and nuclear material accountability for the last 40 years [EI54, GU64, GU70, ANN15.22, AS1458, MA82, IAEA87]. Calorimetric assay is routinely used as a reliable NDA technique for the quantification of plutonium and tritium content. Calorimetric assay of tritium and plutonium-bearing items routinely obtains the highest precision and accuracy of all NDA techniques.
    [Show full text]
  • Two-Dimensional Infrared Spectroscopy of Isotope-Diluted Ice Ih
    http://www.ncbi.nlm.nih.gov/pubmed/21639454. Postprint available at: http://www.zora.uzh.ch Zurich Open Repository and Archive University of Zurich Posted at the Zurich Open Repository and Archive, University of Zurich. Main Library http://www.zora.uzh.ch Winterthurerstr. 190 CH-8057 Zurich www.zora.uzh.ch Originally published at: Perakis, F; Widmer, S; Hamm, P (2011). Two-dimensional infrared spectroscopy of isotope-diluted ice Ih. Journal of Chemical Physics, 134(20):204505. Year: 2011 Two-dimensional infrared spectroscopy of isotope-diluted ice Ih Perakis, F; Widmer, S; Hamm, P http://www.ncbi.nlm.nih.gov/pubmed/21639454. Postprint available at: http://www.zora.uzh.ch Posted at the Zurich Open Repository and Archive, University of Zurich. http://www.zora.uzh.ch Originally published at: Perakis, F; Widmer, S; Hamm, P (2011). Two-dimensional infrared spectroscopy of isotope-diluted ice Ih. Journal of Chemical Physics, 134(20):204505. Two-dimensional infrared spectroscopy of isotope-diluted ice Ih Abstract We present experimental 2D IR spectra of isotope diluted ice Ih (i.e., the OH stretch mode of HOD in D2O and the OD stretch mode of HOD in H2O) at T = 80 K. The main spectral features are the extremely broad 1-2 excited state transition, much broader than the corresponding 0-1 groundstate transition, as well as the presence of quantum beats. We do not observe any inhomogeneous broadening that might be expected due to proton disorder in ice Ih. Complementary, we perform simulations in the framework of the Lippincott-Schroeder model, which qualitatively reproduce the experimental observations.
    [Show full text]
  • A Stable Isotope Dilution Method for a Highly Accurate Analysis of Karrikins
    Hrdlička et al. Plant Methods (2021) 17:37 https://doi.org/10.1186/s13007-021-00738-1 Plant Methods RESEARCH Open Access A stable isotope dilution method for a highly accurate analysis of karrikins Jakub Hrdlička1,2, Tomáš Gucký3, Johannes van Staden4, Ondřej Novák1* and Karel Doležal1,2 Abstract Background: Karrikins (KARs) are recently described group of plant growth regulators with stimulatory efects on seed germination, seedling growth and crop productivity. So far, an analytical method for the simultaneous targeted profling of KARs in plant tissues has not been reported. Results: We present a sensitive method for the determination of two highly biologically active karrikins (KAR 1 and KAR2) in minute amounts of plant material (< 20 mg fresh weight). The developed protocol combines the optimized extraction and efcient single-step sample purifcation with ultra-high performance liquid chromatography-tandem mass spectrometry. Newly synthesized deuterium labelled KAR1 was employed as an internal standard for the valida- tion of KAR quantifcation using a stable isotope dilution method. The application of the matrix-matched calibration series in combination with the internal standard method yields a high level of accuracy and precision in triplicate, on average bias 3.3% and 2.9% RSD, respectively. The applicability of this analytical approach was confrmed by the suc- cessful analysis of karrikins in Arabidopsis seedlings grown on media supplemented with diferent concentrations of KAR1 and KAR2 (0.1, 1.0 and 10.0 µmol/l). Conclusions: Our results demonstrate the usage of methodology for routine analyses and for monitoring KARs in complex biological matrices. The proposed method will lead to better understanding of the roles of KARs in plant growth and development.
    [Show full text]
  • Januar11981 on the Derivation of a Creep Law from Isothermal Bore Hole
    JANUAR11981 ON THE DERIVATION OF A CREEP LAW FROM ISOTHERMAL BORE HOLE CONVERGENCE BY J. PRIJ J.H.J. MENGELERS ECN does not assume any liability with respect to the use of, or for damages resulting from the use of any information, apparatus, method or process disclosed in this document. Netherlands Energy Research Foundation ECN P.O. Box 1 1755 ZG Petten INH) The Netherlands Telephone (0)2246 - 6262 Telex 57211 ECN-87 SEPTEMBER 1980 DISPLACEMENT AND EXCHANGE REACTIONS IN RADIOANALYSIS BY P.C.A. OOMS Proefschrift Vrije Universiteit Amsterdam, 30 september I980 - J CONTENTS Page CHAPTER 1. INTRODUCTION 9 1.1. Classification of separation methods 10 1.7.1. Reaction with a free reagent 10 1.1.2. Displacement 11 1.1.3. Isotopic exchange 12 1.2. Analytical criteria 12 1.2.1. Activation analysis with a spe­ cific reagent 13 1.2.2. Isotope dilution analysis with a specific reagent 14 1.2.3. Activation analysis with a non­ specific reagent 14 1.2.4. Isotope dilution with a non-speci­ fic reagent 14 1.2.5. Isotopic exchange 14 1.3. Selection of procedures 15 1.3.1. Liquid-liquid extraction using a non-specific chelating agent 16 1.3.2. Amalgams 16 1.3.3. Loaded active carton 18 1.3.4. Coulometry 19 1.4. List of symbols 21 1.5. Summary of contents 23 1.6. References 25 CHAPTER 2. APPLICATION OF DISPLACMENT - AND EXCHANGE REACTIONS IN NEUTRON ACTIVATION AND ISOTOPE DILUTION ANALYSIS 27 2.1. Introduction 28 2.2. Calculations of equilibrium concentrations 28 2.2.1.
    [Show full text]
  • Determination of Selenium in Biological Materials by Stable Isotope Dilution Gas Chromatography-Mass Spectrometry
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln U.S. Department of Agriculture: Agricultural Publications from USDA-ARS / UNL Faculty Research Service, Lincoln, Nebraska 1981 Determination of Selenium in Biological Materials by Stable Isotope Dilution Gas Chromatography-Mass Spectrometry Donald C. Reamer Beltsville Human Nutrition Research Center Claude Veillon Beltsville Human Nutrition Research Center Follow this and additional works at: https://digitalcommons.unl.edu/usdaarsfacpub Part of the Agricultural Science Commons Reamer, Donald C. and Veillon, Claude, "Determination of Selenium in Biological Materials by Stable Isotope Dilution Gas Chromatography-Mass Spectrometry" (1981). Publications from USDA-ARS / UNL Faculty. 309. https://digitalcommons.unl.edu/usdaarsfacpub/309 This Article is brought to you for free and open access by the U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Publications from USDA-ARS / UNL Faculty by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 2166 Anal. Chem. 1981, 53, 2166-2169 Table 11. Ionization Range Ri for Electrons pendence on electron energy and the nature of the target gas are in accord with expectations from considerations of stopping He Ne Ar Kr Xe N, aira power, energies required to form an ion pair, and ionization 300 eV cross sections. Ri9,,pg/cmZ n.d. n.d. 1.55 2.74 3.43 1.24 1.63 LITERATURE CITED Ri,,, cm at -- -- 0.61 0.51 0.41 0.69 0.88 (1) Cole, A. Radiat. Res. 1969, 38, 7. 1 torr, (2) Polley, C. W., Jr.; Illies, A.
    [Show full text]
  • Determination of Lithium in Human Serum by Isotope Dilution Atomic Absorption Spectrometry
    Determination of lithium in human serum by isotope dilution atomic absorption spectrometry Alexander Winckelmann1,2, Dalia Morcillo1,2, Silke Richter2, Sebastian Recknagel2, Jens Riedel2, Jochen Vogl2, Ulrich Panne1,2, Carlos Abad2* 1Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Str. 2, 12489 Berlin, Germany 2Bundesanstalt für Materialforschung und –prüfung (BAM), Richard-Willstätter-Str. 11, 12489 Berlin, Germany *E-mail corresponding author: [email protected] Abstract The therapeutic dose of lithium (Li) compounds, which are widely used for the treatment of psychiatric and hematologic disorders, is close to its toxic level; therefore, drug monitoring protocols are mandatory. Herein, we propose a fast, simple, and low-cost analytical procedure for the traceable determination of Li concentration in human serum, based on the monitoring of the Li isotope dilution through the partially resolved isotope shift in its electronic transition around 670.80 nm using a commercially available high-resolution continuum source graphite furnace atomic absorption spectrometer. With this technique, serum samples only require acidic digestion before analysis. The procedure requires three measurements—an enriched 6Li spike, a mixture of a certified standard solution and spike, and a mixture of the sample and spike with a nominal 7Li/6Li ratio of 0.82. Lanthanum has been used as an internal spectral standard for wavelength correction. The spectra are described as the linear superposition of the contributions of the respective isotopes, each consisting of a spin-orbit doublet, which can be expressed as Gaussian components with constant spectral position and width and different relative intensity, reflecting the isotope ratio in the sample. Both, the spectral constants and the correlation between isotope ratio and relative band intensity have been experimentally obtained using commercially available materials enriched with Li isotopes.
    [Show full text]
  • Determination of Creatinine in Human Serum by Isotope Dilution-Mass Spectrometry : Definitive Methods in Clinical Chemistry, IV I \ by L
    L. Siekmann: Determination of creatinine by isotope dilution-mass spectrometry \ 37 J. Clin. Chem. Clin. Biochem. Vol. 23. 1985, pp. 137-144 Determination of Creatinine in Human Serum by Isotope Dilution-Mass Spectrometry : Definitive Methods in Clinical Chemistry, IV i \ By L. Siekmann i Institut für Klinische Biochemie, Universität Bonn jl l (Received September 12/October 29, 1984) Summary: A method for the determination of creatinine in human serum by isotope dilution-mass spectrometry is described. The analytical procedure comprises the following Steps: (1) Addition of [13C,15N2]creatinine to the serum sample; (2) ion exchange chromatography on the cation exchange resin AG 50W-X2; (3) formation of the trimethylsilyl derivative; (4) gas liquid chromatography-mass spectrometry (GC-MS); selected ion monitoring (SIM) at the m/z-values 329 and 332; (5) calculation of the amount of creatinine in the serum sample from the isotope ratio, äs measured by GC- MS. 13 15 [ C, N2]Creatinine was prepared by chemical synthesis. The substance is then used äs internal Standard for the measurement of creatinine in serum samples. The imprecision of the method was in the ränge from 0.35 to 1.05% (coefficient of Variation) äs determined by repetitive measurements of creatinine in 13 different control sera on different pccasions. The lower limit of detection of the mass spectrometer in the selected ion monitoring mode is about 0.5 ng creatinine with a signal to noise ratio of 3: l The accuracy of the method is achieved by the use of the isotope dilution principle in combination with GC- MS.
    [Show full text]
  • Isotope Dilution Spaces in Mice 2841 Regulated at 30±1 ¡C and the Photoperiod Was 16 H:8 H L:D
    The Journal of Experimental Biology 202, 2839–2849 (1999) 2839 Printed in Great Britain © The Company of Biologists Limited 1999 JEB2221 ISOTOPE DILUTION SPACES OF MICE INJECTED SIMULTANEOUSLY WITH DEUTERIUM, TRITIUM AND OXYGEN-18 ELZBIETA KRÓL AND JOHN R. SPEAKMAN* Aberdeen Centre for Energy Regulation and Obesity, Department of Zoology, University of Aberdeen, Aberdeen AB24 2TZ, UK *Author for correspondence (e-mail: [email protected]) Accepted 28 July; published on WWW 30 September 1999 Summary The isotope dilution technique for measuring total body reproductive mice. In addition, the hydrogen tracer water (TBW), and the doubly labelled water (DLW) employed had a significant effect (deuterium spaces were method for measuring energy expenditure, are both 2.0 % larger than tritium spaces). Deuterium and tritium sensitive to small variations in the ratio of the hydrogen to dilution spaces, expressed as a percentage of body mass, oxygen-18 dilution space. Since the dilution space ratio were highly correlated. Dilution space ratios ranged from varies between individuals, there has been much recent 0.952 to 1.146 when using deuterium, and from 0.930 to debate over what causes this variability (i.e. physiological 1.103 when using tritium. Dilution space ratios based on differences between individuals or analytical error in the deuterium and tritium were also highly correlated. isotope determinations), and thus which values (individual Comparison of standard deviations of the dilution space or a population mean dilution space ratio) should be ratio based on deuterium in vivo and in vitro indicated that employed for TBW and DLW calculations. To distinguish only 4.5 % of the variation in the dilution space ratios between physiological and analytical variability, we observed in the mice could be accounted for by analytical injected 15 non-reproductive and 12 lactating mice (Mus variation in the deuterium and oxygen-18 analyses.
    [Show full text]
  • Sk98k0228 Utilization of Atomic Emission Spectroscopy
    P31 SK98K0228 UTILIZATION OF ATOMIC EMISSION SPECTROSCOPY METHODS FOR DETERMINATION OF RARE EARTH ELEMENTS Jana Kubova, Jozefa Polakovicova, Jan Medved', Vladimir Stresko, Geological Institute, Faculty of Natural Sciences, Bratislava The intensive priority of utilization of the rare earth elements (REE) has started since seventy years. The great importance of high purity compounds of REE has found their utilization first of all in electrical industry, nuclear energetics, optics, ceramics, engineering, chemical industry and other. The importance of data on REE for petrogenetic classification of rocks since it provides information on magma differentiation and the metamorphic or other geochemical processes is well recognized [1]. The new analytical techniques and procedures which were developed in eighties for determination of ultra-trace contents of REE have led to their wide popularization not only for many geochemical and petrogenetic investigations but for the environment monitoring as well. Requests for REE determination have therefore become common in most geoanalytical laboratories in spite of the fact that analysis of usual concentration levels is in the least not a simple task. Many years ago only two analytical techniques, namely neutron activation analysis (NAA) and isotope dilution mass spectrometry (EDMS), were available for the determination of REE at chondritic abundance levels in rocks and minerals, but use of these techniques remained confined to a few well-established laboratories, mainly because of the high cost of the equipment. In the seventies, inductively coupled plasma (ICP) spectrometry had a great impact in this field in its optical version and more recently in its ICP-MS form [2-4]. Despite considerable progress in REE determination as witnessed by numerous publications, several problems have still remained and may cause errors if not properly handled.
    [Show full text]
  • Method 6800: Elemental and Molecular Speciated Isotope
    METHOD 6800 ELEMENTAL AND MOLECULAR SPECIATED ISOTOPE DILUTION MASS SPECTROMETRY SW-846 is not intended to be an analytical training manual. Therefore, method procedures are written based on the assumption that they will be performed by analysts who are formally trained in at least the basic principles of chemical analysis and in the use of the subject technology. In addition, SW-846 methods, with the exception of required method use for the analysis of method-defined parameters, are intended to be guidance methods which contain general information on how to perform an analytical procedure or technique which a laboratory can use as a basic starting point for generating its own detailed standard operating procedure (SOP), either for its own general use or for a specific project application. The performance data included in this method are for guidance purposes only, and are not intended to be and must not be used as absolute quality control (QC) acceptance criteria for purposes of laboratory accreditation. 1.0 SCOPE AND APPLICATION For a summary of changes in this version from the previously published draft method 6800, February 2007 Rev 0, please see Appendix A at the end of this document. 1.1 This method consists of two approaches: (1) isotope dilution mass spectrometry (IDMS) for the determination of the total concentrations of elements and molecules and (2) molecular speciated isotope dilution mass spectrometry (SIDMS) for the determination of elemental and molecular species. IUPAC defines speciation analysis as “analyzing chemical compounds that differ in isotopic composition, conformation, oxidation or electronic state, or in the nature of their complexed or covalently bound substituents, which can be regarded as distinct chemical species.” This method is applicable to the determination of total elements as well as elemental species and molecular species at parts per billion (ppb), parts per trillion (ppt) and sub-ppt levels in samples of various types; in waters, solids, blood, foods or in extracts or digests.
    [Show full text]