Atomic emission detection

Atomic Emission Detection Limits for Selected Elements... 

Figure 2.19 Schematic representation of an on-line liquid-liquid extraction-GC/AED system. Reprinted from Journal of High Resolution Chromatography, 18, E. C. Goosens et al, Continuous liquid-liquid extraction combined on-line with capillary gas chromatography- atomic emission detection for environmental analysis , pp. 38-44, 1995, with permission from Wiley-VCH.

Janak K, G Becker, A Colmsjo, C Ostman, M Athanasiadou, K Valters, A Bergman (1998) Methyl sulfonyl polychlorinated biphenyls and 2,2-bis(4-chlorophenyl)-l,l-dichloroethene in gray seal tissues determinated by gas chromatography with electron capture detection and atomic emission detection. Environ Toxicol Chem 17 1046-1055. 

The presence of heteroatoms usually provides a convenient feature for improving selectivity by employing selective detection mechanisms. GC may then use flame photometric detection (FPD) for S and P atoms and to a certain extent for N, Se, Si etc. thermoselective detection (TSD) and nitrogen-phosphorus detection (NPD) for N and P atoms electron capture detection (ECD) for halogen atoms (E, Cl, Br, and 1) and for systems with conjugated double bonds and electron-drawing groups or atomic emission detection (AED) for many heteroatoms. 

The most widely regarded approach to accomplish the determination of as many pesticides as possible in as few steps as possible is to use MS detection. MS is considered a universally selective detection method because MS detects all compounds independently of elemental composition and further separates the signal into mass spectral scans to provide a high degree of selectivity. Unlike GC with selective detectors, or even atomic emission detection (AED), GC/MS may provide acceptable confirmation of the identity of analytes without the need for further information. This reduces the need to re-inject a sample into a separate GC system (usually GC/MS) for pesticide confirmation. Through the use of selected ion monitoring (SIM), efficient ion-trap or quadrupole devices, and/or tandem mass spectrometry (MS/MS), modern GC/MS instruments provide LODs similar to or lower than those of selective detectors, depending on the analytes, methods, and detectors. 

Three different detection methods (gas chromatography with electron capture, mass spectrometric and atomic emission detectors) have been compared for the determination of polychlorobiphenyls in highly contaminated marine sediments [74], Only atomic emission detection in the chlorine-selective mode provided excellent polychlorobiphenyl profiles without interferences. However, the lower sensitivity of the atomic emission detector, compared to the other two detectors required a 10 to 20g sample size for most analyses. 

A method with LOQ at ppt levels was developed based on LLE followed by GC-AFID for the determination of trace concentrations of nitrobenzene, l-chloro-2-nitrobenzene and synthetic fragrances such as musk xylene (223) and musk ketone (224). The method was applied to study the distribution of these compounds in environmental samples of North Sea waters460. GC with atomic emission detection (AED) has been successfully applied to the determination of nitro musks in human adipose tissues, at ppb concentration levels. A clean-up procedure for nonpolar substances and element-specific detection with AED enabled for the first time target screening analysis for lipophilic nitro aromatic compounds. The lack of sensitivity of AED was compensated by higher concentrations of the extracts... 

Organotin compounds enriched from a diethylether extract of a snow sample collected from the city of Gdansk, Poland and analyzed are shown in Fig. 22 b, c [286]. Gas chromatography with atomic emission detection (GC-AED) run in the chlorine and tin channels, respectively, revealed the presence of tributyltin chloride and this was subsequently confirmed by GC-MS and GC-AED analyses of an internal standard solution (e.g., 1-chlorooctane) of that compound. Quantification was based on the response to chlorine (wavelength 479 nm) in the AED system, and a detection limit of 0.5-1 ng/1 was achieved for all the reference substances. 

Galvanostatic current-pulse method, 38 29, 33 Galvanostatic technique hydrocarbon adsorption, 30 256 surface coverage, 30 299-300 Gamma emission, 26 124, 125, 127 Garin-Gault mechanism, 30 20, 23 Gas chromatography -atomic emission detection... 

Nitrogen compounds in middle distillates can be detected selectively by chemiluminescence. Individual nitrogen compounds can be detected down to 100 ppb nitrogen. Gas chromatography with either sulfur chemiluminescence detection or atomic emission detection has been used for sulfur-selective detection. 

Schematic diagram of a gas chromatography atomic emission detection (GC-AED) instrument.

Eisert R, Levsen K, Wuensch G. 1994. Element-selective detection of pesticides by gas chromatography atomic-emission detection and solid-phase microextraction. J Chromatogr 683(1) 175-183. 

Hankemeier TH, Louter AJH, Rinkema FD, et al. 1995. On-line coupling of solid-phase extraction and gas chromatography with atomic emission detection for analysis of trace pollutants in aqueous samples. Chromatographia 40(3-4) 119-124. 

I. Rodriguez Pereiro and A. Carro Diaz, Speciation of mercury, tin and lead compounds by gas chromatography with microwave-induced plasma and atomic-emission detection (GC-MIP-AED), Anal. Bioanal. Chem., 312, 2002, 74-90. 

A. M. Carro, I. Neira, R. Rodil and R. A. Lorenzo, Speciation of mercury compounds by gas chromatography with atomic emission detection. Simultaneous optimisation of a headspace solid-phase microextraction and derivatisation procedure by use of chemometric techniques, Chro-matographia, 56(11/12), 2002, 733-738. 

Fig. 2. Separation and analysis of polyaromatic sulfur-containing compounds (PASC). Oils 3-1, 3-2, and 3-3 were analyzed by gas chromatography-mass spectroscopy (GC-MS) and gas chromatography-atomic emission detection (GC-AED). Reproduced from Ref. 12, with permission.

ACS American Chemical Society AED atomic emission detection AEDA aroma extract dilution analysis AMC 7-amido-4-methylcoumarin ANS anilinonapththalene sulfonate AOAC Association of Official Analytical Chemists... 

Olson, N. and R. Carrell (1995). Atomic emission detection for gas chromatographic analysis of nitrogen-containing herbicides in water. J. Assoc. Off. Anal. Chem. Int., 78(6) 1464-1473. 

In recent years plasma MS has become very popular, especially where the ion source for the mass spectrometer is an ICP. These systems, which are available commercially, offer detection limits two to three orders of magnitude better than those for atomic emission detection (i.e. subpicogram levels for some elements)... 

The rapid separation capability of CZE for ions in solution and its low sample volumes and flow rates mean it is excellent for speciation studies, and Dabek-Zlotorzynaska et al (1998) have written a comprehensive review of the field. Hybrid techniques with CZE are still novel and work is concentrating on perfecting the interfaces which must be able to cope with rapid separations and very low sample volumes. A helium MIP with atomic emission detection has been coupled to CZE an ion-exchange membrane capillary was used to connect the separation capillary to the interfacing capillary (Liu and Lopez Avila, 1993). CZE... 

Quimby, B.D. and Sullivan, J.J. (1990) Evaluation of a microwave cavity, discharge tube and gas flow system for combined gas chromatography-atomic emission detection. Anal. Chem., 62, 1027-1034. 

All alternative detection schemes fail in at least one of the above criteria, and mass spectrometric detection has replaced other detectors even in applications in which they were well established, such as ECD for the gas chromatographic determination of organochlorine pesticides,61 or atomic emission detection (AED) or FPD in the GC analysis of organotin (OT) compounds.62... 

Perez-Sirvent, C. and M.-J. Martlnez-Sanchez. 2007. Comparison of two derivatizing agents for the simultaneous determination of selenite and organoselenium species by gas chromatography and atomic emission detection after preconcentration using solid-phase microextraction. J. Chromatogr. A 1165 191-199. 

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