Isotope dilution mass spectroscopy

Two other techniques that depend only on base SI units are coulometry and isotope-dilution mass spectrometry. Coulometry is discussed in Chapter 11. Isotope-dilution mass spectroscopy is beyond the scope of an introductory text, however, the list of suggested readings includes a useful reference. 

Table 1 Metrological properties of methods used by the Choles- CV coefficient of variation, HDLC high-density lipoprotein cho-terol Reference Method Laboratory Network (CKMLN). 2 KM lesterol, SD standard deviation, LDLC low-density lipoprotein Secondary reference method, DCM designated comparison meth- cholesterol, NA not available od, IDMS isotope dilution mass spectroscopy, AK Abell-Kendall,...

Definite Method. The definitive method for total calcium measurement is isotope dilution mass spectroscopy [9]. It has strict performance guidelines and is the accuracy standard against which all methods should be compared. 

Isotope Dilution Mass Spectroscopy (IDMS) <1.0 Any matrix Michiels and DeBievre (1986) — Suitable for absolute determination of cadmium in reference materials expensive. 

IKES. ion kinetic energy spectroscopy IRMS. isotope ratio mass spectrometry ISDMS. isotope dilution mass spectrometry ITMS. ion trap mass spectrometry LA. laser ablation... 

Ultraviolet spectroscopy has been applied to the determination of lead and lead speciation studies [407]. Scaule and Patterson [408] used isotope dilution-mass spectrometry to determine the lead profile in the open North Pacific Ocean. 

Various spectroscopic techniques such as flame photometry, emission spectroscopy, atomic absorption spectrometry, spectrophotometry, flu-orimetry, X-ray fluorescence spectrometry, neutron activation analysis and isotope dilution mass spectrometry have been used for marine analysis of elemental and inorganic components [2]. Polarography, anodic stripping voltammetry and other electrochemical techniques are also useful for the determination of Cd, Cu, Mn, Pb, Zn, etc. in seawater. Electrochemical techniques sometimes provide information on the chemical species in solution. 

Several spectroscopic methods have been used to monitor the levels of heavy metals in man, fossil fuels and environment. They include flame atomic absorption spectrometry (AAS), atomic emission spectroscopy (AES), graphite furnace atomic absorption sp>ectrometry (GFAAS), inductively coupled plasma-atomic emission sp>ectroscopy (ICP/AES), inductively coupled plasma mass spectrometry (ICP/MS), x-ray fluorescence sp>ectroscopy (XRFS), isotope dilution mass spectrometry (IDMS), electrothermal atomic absorption spectrometry (ETAAS) e.t.c. Also other spectroscopic methods have been used for analysis of the quality composition of the alternative fuels such as biodiesel. These include Nuclear magnetic resonance spectroscopy (NMR), Near infrared spectroscopy (NIR), inductively coupled plasma optical emission spectrometry (ICP-OES) e.t.c. 

There are three techniques used for the determination of chromium in tissues and body fluids (1) neutron activation analysis (NAA), (2) isotope dilution mass spectrometry (IDMS), and (3) electrothermal atomic absorption spectroscopy (ETAAS). 

A recent review by Balaram gives an account of the various instrumental techniques used in geological analysis. These include atomic absorption spectroscopy and inductively coupled plasma atomic emission spectroscopy as well as X-ray fluorescence, isotope dilution mass spectrometry and neutron activation analysis in addition to recent developments in inductively coupled plasma mass spectrometry especially in rare earth element analysis. 

There are many references to the speciation of organotin compounds (particularly butyltin compounds) in marine sediments (see below), when compounds Uu Snk4 are separated by GLC or HPLC and analyzed by mass spectroscopy (MS),56 sometimes with isotope dilution.57-59... 

Mass balance measurements for 41 elements have been made around the Thomas A. Allen Steam Plant in Memphis, Tenn. For one of the three independent cyclone boilers at the plant, the concentration and flow rates of each element were determined for coal, slag tank effluent, fly ash in the precipitator inlet and outlet (collected isokinetically), and fly ash in the stack gases (collected isokinetically). Measurements by neutron activation analysis, spark source mass spectroscopy (with isotope dilution for some elements), and atomic adsorption spectroscopy yielded an approximate balance (closure to within 30% or less) for many elements. Exceptions were those elements such as mercury, which form volatile compounds. For most elements in the fly ash, the newly installed electrostatic precipitator was extremely efficient. 

The flameless atomic absorption method has a reproducibility of about 2% or better for homogeneous specimens. Checks (3) between AA and NAA (with radiochemical separation after irradiation) and isotope dilution spark source mass spectroscopy on thoroughly homogenized tuna fish and Bureau of Mines round-robin coal specimens indicate good agreement between the methods. (0.425 0.9%, 0.45 3.5%, and 0.45 4.4% for tuna by AA, NAA, and SSMS, respectively, and 1.004 is the average ratio of NAA to AA results for five coal samples.) The similar results indicate that the technique used in sample preparation... 

Determination of oxidized amino acids in urine is usually performed by isotope dilution gas chromatography-mass spectrometry (L9). DOPA is estimated by HPLC separation of acid protein hydrolysates with fluorescence detection (excitation 280 nm, emission at 320 nm) (A15). Other methods are based on borate-hydrochloric acid difference spectroscopy (this method suffers interference from tyrosine and tryptophan) (W2), derivatization of DOPA with nitrite and subsequent coulometric determination (W3), and fluorometric detection after derivatization with ethylenediamine (A15). 3-Hydroxylysine is quantitated by HPLC with 9-fluorenylmethyl chloroformate precolumn derivatization (M25) of amino acids obtained by gas-phase hydrolysis of proteins (F21). Other general methods to detect amino acid damage are mass spectometry methods applied to protein hydrolysates, such as tandem mass spectrometry (F6). 

Mass spectroscopy is the basic technique used for isotopic analysis. It is also used to determine the concentrations for fissile elements in samples that have been diluted and thus contain too little uranium and plutonium for accurate assay by standard wet chemical techniques. A tracer technique, known as isotope dilution analysis, is used in such cases, particularly with irradiated spent fuel or resin bead samples. 

The epoxide metabolites of inhaled 1,3-butadiene, used in industry, are reported to be carcinogenic and mutagenic in rodents, and their in vivo concentration following inhalation exposure to butadiene has to be determined by gas chromatography/mass spectroscopy, the isotope dilution method utilizing 8 as an internal standard. Commercially available [De]-propylene oxide has been used previously as an internal standard to monitor in vivo blood propylene oxide levels following inhalation exposure to propylene. ... 

A number of less commonly used analytical techniques are available for determining PAHs. These include synchronous luminescence spectroscopy (SLS), resonant (R)/nonresonant (NR)-synchronous scan luminescence (SSL) spectrometry, room temperature phosphorescence (RTP), ultraviolet-resonance Raman spectroscopy (UV-RRS), x-ray excited optical luminescence spectroscopy (XEOL), laser-induced molecular fluorescence (LIMP), supersonic jet/laser induced fluorescence (SSJ/LIF), low- temperature fluorescence spectroscopy (LTFS), high-resolution low-temperature spectrofluorometry, low-temperature molecular luminescence spectrometry (LT-MLS), and supersonic jet spectroscopy/capillary supercritical fluid chromatography (SJS/SFC) Asher 1984 Garrigues and Ewald 1987 Goates et al. 1989 Jones et al. 1988 Lai et al. 1990 Lamotte et al. 1985 Lin et al. 1991 Popl et al. 1975 Richardson and Ando 1977 Saber et al. 1991 Vo-Dinh et al. 1984 Vo- Dinh and Abbott 1984 Vo-Dinh 1981 Woo et al. 1980). More recent methods for the determination of PAHs in environmental samples include GC-MS with stable isotope dilution calibration (Bushby et al. 1993), capillary electrophoresis with UV-laser excited fluorescence detection (Nie et al. 1993), and laser desorption laser photoionization time-of-flight mass spectrometry of direct determination of PAH in solid waste matrices (Dale et al. 1993). 

This H/D substitution has conversely appreciable effects on the dynamics of H-bonds that are sensitive to the doubling of the mass of the H-atom that establishes an H-bond. It appears particularly well in vibrations and can consequently be used in vibrational spectroscopy, particularly IR spectroscopy, to convey original information on H-bonds. Isotopic dilution techniques can then be most interesting either to decouple the vibration of a particular H-bond from that of surrounding H-bonds that display resonant vibrations, thus... 

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