BCD - Electron-capture

Ceph - Cephapirin Ox - oxacillin, Amp - ampicillin, BCD - Electron capture detection... 

Abbreviations GC, gas chromatography BCD, electron capture detection FID, flame ionization detee-tion MS, mass speetrometry PID, photoionization deteetion... 

BCD—electron capture detector Ed.—editor(s) or edited by Edn—edition... 

Abbreviations FID flame ionization detector BCD electron capture detector FPD flame photometric detector MS mass spectrometer MED microwave emission detector AAS atomic absorption spectrometer. 

HA, heterocyclic amine AA, aromatic amine PA, polyamine Al, aliphatic amine N, nitrosamine MAM, Musk amino metabolities ABDACs, alkylbenzyldimethylammonium chlorides BCD, electron capture detection AED, atomic emission detection FID, flame ionization detection FPD, flame photometric detection GC-MS-SIM, GC-MS selected ion monitoring NPD, nitrogen phosphorus detection NlCl, negative-ion chemical ionization El, electron ionization CGC, capihary GC A, air H, water W, waste. 

Information for acertain parameter not available, if not given, na, not available DI, deionized water Cl, chemical ionization BCD, electron capture detector El, electron impact ionization FID, flame ionization detector MS, mass spectrometer MtBE, methyl tert-butylether MTBSTE, n-(tert-butyldimethylsilyl)-Wmethylfluoracetamide PDAM, 1-pyrenyldiazomethane PFBBr, pentafluorobenzyl bromide PEBOH, pentafluorobenzyl alcohol SPME, solid-phase microextraction TOPO, tri-n-octylphoshine oxide UASB, upflow anaerobic sludge blanket reactor. 

BCD (electron-capture) Electron affinity. Cl, Br, 1, F, nitrocompounds, conjugated carbonyls 10 -10 g aldrin(s) 10" Cleanup of samples important... 

FIA-FLD flow injection analysis with fluorescence detection, GC gas chromatography, MS mass spectrometry (quadrupole mass filter), BCD electron capture detector, FID flame ionisation detector, LOD limit of detection, HPLC high performance liquid chromatography, TIMS ion trap mass spectrometry... 

The primary method for detecting methyl parathion and metabolites in biological tissues is gas chromatography (GC) coupled with electron capture (BCD), flame photometric (FPD), or flame ionization detection (FID). Sample preparation for methyl parathion analysis routinely involves extraction with an organic solvent (e g., acetone or benzene), centrifugation, concentration, and re suspension in a suitable solvent prior to GC analysis. For low concentrations of methyl parathion, further cleanup procedures, such as column chromatography on silica gel or Florisil are required. 

GC nitrogen-phosphorus detector (NPD), flame photometric detector (FPD), electron capture detector (BCD), flame ionization detector (FID), mass-spectrometric detector (MS)... 

Universal and selective detectors, linked to GC or LC systems, have remained the predominant choice of analysts for the past two decades for the determination of pesticide residues in food. Although the introduction of bench-top mass spectrometers has enabled analysts to produce more unequivocal residue data for most pesticides, in many laboratories the use of selective detection methods, such as flame photometric detection (FPD), electron capture detection (BCD) and alkali flame ionization detection (AFID) or nitrogen-phosphorus detection (NPD), continues. Many of the new technologies associated with the on-going development of instrumental methods are discussed. However, the main objective of this section is to describe modern techniques that have been demonstrated to be of use to the pesticide residue analyst. 

The most common final separation techniques used for agrochemicals are GC and LC. A variety of detection methods are used for GC such as electron capture detection (BCD), nitrogen-phosphorus detection (NPD), flame photometric detection (FPD) and mass spectrometry (MS). For LC, typical detection methods are ultraviolet (UV) detection, fluorescence detection or, increasingly, different types of MS. The excellent selectivity and sensitivity of LC/MS/MS instruments results in simplified analytical methodology (e.g., less cleanup, smaller sample weight and smaller aliquots of the extract). As a result, this state-of-the-art technique is becoming the detection method of choice in many residue analytical laboratories. 

A technique known as selective electron capti sensitization has been used to increase the response of the BCD weakly electron-capturing compounds [117]. In this mode a standard electron-capture detector is used with a supply of makeup gas doped with a specific sensitizing reagent such as oxygen nitrous oxide. In this way the BCD functions as an ion-aoleculSj... 

The activation step can alternatively be performed without gas by means of infrared multiphoton dissociation (IRMPD) or electron capture dissociation (BCD) (Chap. 2.12.2). Both IRMPD and BCD, solely require storage of the ions during their excitation by photons or electrons, respectively. It is one of the most charming properties of FT-ICR-MS/MS that even the accurate mass of the fragment ions can be determined. [216,217]... 

Ni electron capture detector (BCD) Selective (halogens and other electron-withdrawing groups) 5 X 10 °... 

Traditional detectors (i.e., FID electron capture detector, BCD nitrogen-phosphorous detector, NPD) supply only retention data. However, in many cases this is not enough for proper identification of analytes. Application of GC coupled with an MS detector gives much more information (i.e., the mass spectmm of each compound). GC-MS is a well known and frequently used technique that combines the highly effective separation of GC with the high sensitivity and selectivity of MS. Moreover, improvements in analytical instruments based on different types of mass analyzers (ion trap, quadrupole, and TOF) and the development of hybrid Q-TOF has enhanced the analytical capabilities of modem hardware. Different kinds of mass spectrometers are presented in Table 14.2 [119]. 

It was not until the advent of the electron capture detector (BCD) and the development an appropriate BCD cahbration routine when precise and rehable N2O measurements were made possible (Cohen, 1977 BUdns, 1980 Rasmussen et al, 1976 Weiss, 1981). Up to now the use of an BCD in connection with equilibration or purge-and-trap techniques followed by gas chromatographic separation is state of the art for the determination of dissolved NoO (Butler and BUdns, 1991). 

The flame ionization detector (FID), which, for fluorinated compounds, has the advantage of a greater linearity range in spite of its lower sensitivity in comparison with the electron capture detector (BCD), has been extensively applied to organic metal chelates in particular. Comparisons of the different detectors were carried out (Table 1.2) For special analyses such as the determination of SO2 by reaction to SO2F2 with the radioactive F-isotope or by utilization of H-labelled 3-diketon-ates, radiometric measurements for detection are employed ... 

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