Flame ionization detection analysis

M. Mecozzi and Zs. Papai, Application of curve fitting thin-layer chromatography-flame ionization detection analysis of the carbohydrate fraction in marine mucilage and marine snow samples from Italian seas. J. Chromatogr. Sci. 42 (2004) 268-274. 

The special problems for vaUdation presented by chiral separations can be even more burdensome for gc because most methods of detection (eg, flame ionization detection or electron capture detection) in gc destroy the sample. Even when nondestmctive detection (eg, thermal conductivity) is used, individual peak collection is generally more difficult than in Ic or tic. Thus, off-line chiroptical analysis is not usually an option. Eortunately, gc can be readily coupled to a mass spectrometer and is routinely used to vaUdate a chiral separation. 

Reference methods for criteria (19) and hazardous (20) poUutants estabHshed by the US EPA include sulfur dioxide [7446-09-5] by the West-Gaeke method carbon monoxide [630-08-0] by nondispersive infrared analysis ozone [10028-15-6] and nitrogen dioxide [10102-44-0] by chemiluminescence (qv) and hydrocarbons by gas chromatography coupled with flame-ionization detection. Gas chromatography coupled with a suitable detector can also be used to measure ambient concentrations of vinyl chloride monomer [75-01-4], halogenated hydrocarbons and aromatics, and polyacrylonitrile [25014-41-9] (21-22) (see Chromatography Trace and residue analysis). 

Analytical Techniques. Sorbic acid and potassium sorbate are assayed titrimetricaHy (51). The quantitative analysis of sorbic acid in food or beverages, which may require solvent extraction or steam distillation (52,53), employs various techniques. The two classical methods are both spectrophotometric (54—56). In the ultraviolet method, the prepared sample is acidified and the sorbic acid is measured at 250 260 nm. In the colorimetric method, the sorbic acid in the prepared sample is oxidized and then reacts with thiobarbituric acid the complex is measured at - 530 nm. Chromatographic techniques are also used for the analysis of sorbic acid. High pressure Hquid chromatography with ultraviolet detection is used to separate and quantify sorbic acid from other ultraviolet-absorbing species (57—59). Sorbic acid in food extracts is deterrnined by gas chromatography with flame ionization detection (60—62). 

An on-line supercritical fluid chromatography-capillary gas chromatography (SFC-GC) technique has been demonstrated for the direct transfer of SFC fractions from a packed column SFC system to a GC system. This technique has been applied in the analysis of industrial samples such as aviation fuel (24). This type of coupled technique is sometimes more advantageous than the traditional LC-GC coupled technique since SFC is compatible with GC, because most supercritical fluids decompress into gases at GC conditions and are not detected by flame-ionization detection. The use of solvent evaporation techniques are not necessary. SFC, in the same way as LC, can be used to preseparate a sample into classes of compounds where the individual components can then be analyzed and quantified by GC. The supercritical fluid sample effluent is decompressed through a restrictor directly into a capillary GC injection port. In addition, this technique allows selective or multi-step heart-cutting of various sample peaks as they elute from the supercritical fluid... 

Figure 12.20 SFC-GC analysis of a sample of aviation fuel (a) SFC separation into two peaks (b and c) coixesponding GC ttaces of the respective peaks (flame-ionization detection used throughout). Reprinted from Journal of High Resolution Chromatography, 10, J. M. Levy et ah, On-line multidimensional supercritical fluid chromatography/capillary gas chromatography , pp. 337-341, 1987, with permission from Wiley-VCH.

Sodium dodecyl sulfate present in hydrophilic ointments has been determined by TLC on silica gel with flame ionization detection, which was considered better than the colorimetric method. TLC is preferred to HPLC in this case due to the low sensitivity of the refractive index detector that makes difficult the analysis of small amounts of sodium dodecyl sulfate [284]. 

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. 

The reaction mixture is sampled after each reaction cycle and analyzed for purity, reaction progress, and the presence and amount of by-products (if any) formed. Analysis is by gas chromatography (HP 5890 Series II Phenomenex Zebron ZB-1 capillary column, Phenomenex Cat. No. 7HK-G001-36) with flame ionization detection in order to quantify the by-product impurities. The quantity of the byproducts is determined using an external standard calibration method. 

Commonly used methods for the determination of petroleum hydrocarbon contamination in soil are modifications of Environmental Protection Agency method 418.1, which use sonication or a Soxhlet apparatus for analyte extraction and either infrared spectrometry [5] or gas chromatography with flame ionization detection [6-7] for extract analysis. Regardless of the analytical method following the extraction, both modifications use Freon-113, which has been implicated as a cause of ozone depletion. Therefore, alternative methods are being sought for the determination of hydrocarbon contamination in environmental samples that reduce the need for this halogenated solvent. 

Tao QF, Zeng S. 2002. Analysis of enantiomers of chiral phenethylamine drugs by capillary gas chromatography/ mass spectrometry/fLame-ionization detection and precolumn chiral derivatization. J Biochem Biophys Methods 54 103. 

W. Li, Trace analysis of residual methyl methanesulfonate, ethyl methanesulfonate and isopropyl methanesulfonate in pharmaceuticals by capillary gas chromatography with flame ionization detection. Journal of Chromatography A, 2004,1046(1-2), 297-301. 

Methods for Determining Biomarkers of Exposure and Effect. As noted in Section 6.1, methods are available for the qualitative and quantitative measurement of 2-hexanone after it is separated from its sample matrix (Anderson and Harland 1980 Fedtke and Bolt 1986 Nomeir and Abdou-Donia 1985 White et al. 1979). High-resolution gas chromatography for 2-hexanone analysis has been developed to the point that the instrumental capability to separate volatile analytes by HRGC is, for the most part, no longer the limiting factor in their analysis. Flame ionization detection has enabled detection at very low levels and MS has assured specificity in measurement. 

Environmental Protection Agency (USA) emergency response guidebook electron spin resonance field desorption mass spectrometry flow injection analysis flame ionization detection/detector fluorescence detection/detector Xylenol Orange-ferric complex final ozonide... 

Dialkyl peroxides (continued) colorimetry, 707-8 flame ionization detection, 708 NMR spectroscopy, 708 titration methods, 707 UV-visible spectrophotometry, 707-8 enthalpies of reactions, 153-4 graft polymerization initiation, 706 hydroperoxide determination, 685 peroxide transfer synthesis, 824-5 stmctural characterization, 708-16 electrochemical analysis, 715-16 electron diffraction, 713 mass spectrometry, 714 NMR spectroscopy, 709-11 thermal analysis, 714-15 vibrational spectra, 713-14 X-ray crystallography, 711-13 synthesis... 

Chen, X., and B. R. T. Simoneit, Epicuticular Waxes from Vascular Plants and Particles in the Lower Troposphere Analysis of Lipid Classes by Iatroscan Thin-Layer Chromatography with Flame Ionization Detection, . /. Atmos. Chem., 18, 17-31 (1994). 

Porter, K., and D. H. Volman, Flame Ionization Detection of Carbon Monoxide for Gas Chromatographic Analysis, Anal. Chem, 34, 748-749 (1962). 

Selected methods for the analysis of ethylbenzene in various matrices are given in Table 1. Ethylbenzene can be determined in biological material (blood, subcutaneous fat, plant foliage, fish samples) using head-space gas chromatography (GC), GC with mass spectrometry, and GC with flame ionization detection (WHO, 1996a). 

It must be compatible with the analytical method. The frequent use of CS2 as a solvent is favored because CS2 produces a low response when analysis is performed by gas chromatography with flame ionization detection (GC/FID). Likewise, low UV-absorbing solvents are frequently used in high performance liquid chromatography (HPLC) to minimize solvent interference when using a UV detector. 

Purification. a-Methylstyrene was purified by distillation through a 6-foot, Heli-grid-packed, modified Podbielniak column under a reduced pressure of dry helium. Purity of the distillate was established by vapor phase chromatographic analysis, using flame ionization detection and an appropriate column. Sample purity generally ranged from 99.90 to 99.98%. 

Fig. 5.2. Gas chromatography (GC) and electroantennography (EAG) analysis of male Manduca sexta antennal responses to floral volatiles from the night blooming cactus Peniocereus greggii. The upper trace is a flame ionization detection (FID) chromatogram of floral headspace odors separated on a carbowax GC column, while the lower trace is a simultaneous recording of summed antennal action potentials elicited by individual compounds as they elute. The largest absolute responses followed methyl benzoate, methyl salicylate, and benzyl alcohol (peaks 3-5, respectively). Note the poor responses (circled) to benzaldehyde and benzyl benzoate (peaks 2, 6) and the disproportionately higher responses (bold arrows) to methyl salicylate and benzyl salicylate (peak 7) relative to their peak areas. Peak 1 is the internal standard (toluene) remaining unnumbered peaks are ambient contaminants.

Analytical methods used are described by Bianchi et al. (1997). Methods 3M 3500 and 3M 3520 involve absorption onto a butadiene-specific activated charcoal, followed by desorption with carbon disulfide or with dichloromethane, respectively, and analysis by direct-injection gas chromatography with flame ionization detection. 

The United States National Institute for Occupational Safety and Health has approved a method for the analysis of chloroprene in workplace air. The method [Method 1002] involves passing the sample through a solid sorbent tube of coconut shell charcoal, desorbing with carbon disulfide, and analysis by gas chromatography with flame ionization detection. The estimated limit of detection for this method is 0.03 mg per sample or 3.8 mg/m3 assuming a maximum air sample of 8 L (Eller, 1994). 

Sample Concentration Experiments. A CLLE quality assurance blank was run by extracting 90 L of Milli-Q water with three CLLE samplers in a parallel configuration and concentrating the composited extract to 4 mL by Kudema-Danish evaporation. The 22,500-fold concentrate was analyzed by GC-flame ionization detection (GC-FID) and GC-MS. Thirty-two peaks were observed by using GC-FID analysis, but because of their low concentrations, only four contaminants were identified by GC-MS cyclohexene, 2-cyclohexen-1-one, n-butyl phthalate, and bis(2-ethylhexyl) phthalate. Cyclohexene is a solvent preservative that has been identified in commercial high-purity methylene chloride (16), and 2-cyclohexen-l-one is its air oxidation product. The phthalates are ubiquitous laboratory contaminants and have also been identified in commercial methylene chloride (17). 

Ratnayake, W.M.N. and Ackman,R.G. 1985. Rapid analysis of Canola gum lipid composition by Iatroscan thin layer chromatography-flame ionization detection. Can. Inst. Food Sci. Technol. J. 18 284-289. 

Static headspace GC involves heating the sample in an air-tight environment until the volatile lipids in the food reach an equilibrium with those in the surrounding air. The air above the sample (headspace) is then sampled and analyzed. Flame ionization detection (GC-FID) can be used for quantification and mass-selective detection (GC-MS) can be used for compound identification. This protocol also outlines semiquantitative and quantitative approaches for determination of volatile lipid concentration, and is particularly designed for analysis of a meat sample. 

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