Multi-element detection

ICP is intolerant to the solvents commonly used in LC development. Consequently, most LC-ICP-AES systems have been employed with ion-exchange columns, as this separation process largely involves aqueous mobile phases that are amenable to the ICP-AES instrument. Use of acetonitrile or THF in the mobile phase has usually evoked a change in interface design to accommodate the different solvents. The advantages of LC-ICP-AES include multi-element detection and the ability to obtain real-time chromatograms. LC-ICP-AES... 

Carey, J.M., Vela, N.R and Caruso, J.A. (1992) Multi-element detection for supercritical fluid chromatography by inductively coupled mass spectrometry./. Anal. At. Spectrom., 7, 1173-1181. 

Kumar, U.T., Vela, N.P. and Caruso, J.A. (1995) Multi-element detection of organometals by supercritical fluid chromatography with inductively coupled plasma mass spectro-metric detection. /. Chromatogr. Sci., 33, 606-610. 

The second major environmental application of FFF has been the use of an element-specific detector, usually in series with a UV detector, to provide elemental composition data along with the PSD. Graphite-furnace atomic absorption spectrometry has been used off-line on fractions collected from the FFF run. However, the multi-element detection, low detection limits and capability to function as an online detector have made inductively coupled plasma mass spectrometry (ICP-MS) the ideal detector for FFE85-86 The sample introduction system of the ICP-MS is able to efficiently transport micron-sized particles into the high-temperature plasma,... 

The association of a spectrometer with a liquid chromatograph is usually to aid in structure elucidation or the confirmation of substance identity. The association of an atomic absorption spectrometer with the liquid chromatograph, however, is usually to detect specific metal and semi-metallic compounds at high sensitivity. The AAS is highly element-specific, more so than the electrochemical detector however, a flame atomic absorption spectrometer is not as sensitive. If an atomic emission spectrometer or an atomic fluorescence spectrometer is employed, then multi-element detection is possible as already discussed. Such devices, used as a LC detector, are normally very expensive. It follows that most LC/AAS combinations involve the use of a flame atomic absorption spectrometer or an atomic spectrometer fitted with a graphite furnace. In addition in most applications, the spectrometer is set to monitor one element only, throughout the total chromatographic separation. 

Jones P, Williams T, Ebdon L. 1990. Development of a novel multi-element detection system for trace metal determination based on chemiluminescence after separation by ion chromatography. Anal Chim Acta 237 291-298. 

For the above reasons, indoor air filters often yield particle masses that are orders of magnitude below the mass requirements for quantitative ED-XRF analysis - the multi-element detection method traditionally used for air analysis. Researchers are currently seeking alternative multi-element analytical techniques with adequate sensitivity for indoor air samples. Indoor and outdoor air concentration data, from a variety of studies which employed different sampling and analytical approaches, are summarized in Table 11.3. Van Winkle and Scheff (2001) used high-volume samplers equipped with 37-mm quartz fiber filters and an air flow rate of 25 L min to monitor 10 homes in... 

Although the presently realised continuum-source AA spectrometers are still operated sequentially for multi-element detection, it may be anticipated that, with use of suitable optics and multi-array detectors, this method wiU become a truly simultaneous multi-element technique [10]. 

Synchrotron Radiation as a Source for Infrared Microspectroscopic Imaging with 2D Multi-Element Detection... 

ICP-OES has the advantage of multi-elemental detection capability and offers a wide linear dynamic range. However, the introduction of organic solvents, such as fuels cause plasma destabilization or even plasma extinction and the use of ICP accessories may be necessary, such as direct injection nebulizer, ultrasonic nebulizer with micro-porous membrane... 

Note The analytical problems of inorganic MS often require only certain selected isotopes or narrow m/z ranges to be measured. Multicollector systems, for example, are adjusted to simultaneously detect a few isotopes for the purpose of accurate isotope ratio determinations or to quantify a low-abundant isotope together with an isotopic standard for internal reference. Thus, the data is more often presented in tabular form or in plots of concentration versus variables such as depth of invasion, age of samples, or location on a surface. Mass spectra covering a wider range are only acquired for survey multi-element detection. 

Benkhedda et al demonstrated the unique performance of ICP-TOF-MS for the simultaneous multi-element detection of 22 isotopes of rare earth elements (REEs) in a El peak of about 5 s width (at 50% height) without the introduction of any spectral skew. Eigure 2.24 represents the profiles obtained by USN-ICP-TOE-MS for three replicates of 250 ptL injections of a 0.1 mg/L multi-elemental standard of REE s after FI on-line pre-concentration in a fkr (KR) pre-coated with the chelating reagent l-phenyl-3-methyl-4-benzoyl-pyrazol-5-one (PMBP). 

Minganti, V., Capelli, R., and DePellegrini, R. (1995) Evaluation of different derivatization methods for the multi-element detection of Hg, Pb and Sn compounds by gas... 

The linear dynamic range of an ICP-MS instrument is typically about 4-6 orders of magnitude, while the sensitivity is often 3 orders of magnitude better than the ICP-AES technique. While the detection limits for many elements with ICP-MS are better or comparable to AES and graphite furnace atomic absorption spectrometry, the simultaneous multi-elemental detection afforded by ICP-MS clearly places this technique in the lead for analytical utility and versatility. 

Specific multi-element monitoring is possible in various ways. Sequential switching between elemental wavelengths of a monochromator is useful if speed is compatible with peak elution rates [5]. However, the most widely utilized multi-element detection has been by means... 

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