Environmental applications, capillary

Environmental Analysis One of the most important environmental applications of gas chromatography is for the analysis of numerous organic pollutants in air, water, and wastewater. The analysis of volatile organics in drinking water, for example, is accomplished by a purge and trap, followed by their separation on a capillary column with a nonpolar stationary phase. A flame ionization, electron capture, or... 

Identification of components in environmental samples and in samples from laboratory studies of biodegradation and biotransformation is generally based on the application of MS coupled to either GC or LC systems. For environmental samples which may contain only small amounts of the relevant compounds, MS is particularly attractive in view of the extremely small amounts of samples — of the order of nanograms — which are required. An important additional advantage is that since the mass spectrometer can be interfaced with GC, LC, or capillary electrophoresis (CE) systems which incorporate separation procedures, pure samples are not required. Some salient issues in MS in the context of environmental application are summarized briefly as an introduction. Reference should be made to an exhaustive review (Burlingame et al. 1998) for instrumental details and aspects that are not covered here, such as MS of synthetic and natural polymers. 

L.J. Gimbert, P.J. Worsfold, Environmental applications of liquid-waveguide-capillary cells coupled with spectroscopic detection, Trends Anal. Chem. 26 (2007) 914. 

An overview of capillary gas chromatography is presented. Selected environmental applications, such as PCB s in water, PAH s in airborne particulate matter, and TCDD s at the part-per-trillion level illustrate the separation and analysis of complex mixtures. The chromatographic performance, characteristics, and trade-offs of packed and capillary columns are described in terms of permeability and efficiency, sample capacity, choice of stationary phase, high temperature capabilities, quantitative accuracy, and the development of GC separation methods. 

Pedersen-Bjergaard, S.. Greibrokk, T., 1996. Environmental applications of capillary gas chromatography coupled with atomic emission detection - a review. J. High Res. Chrom. 19, 597-607. 

The small pathlength defined by the capillary internal diameter coupled with the need of a small injection volume to preserve the high-resolution features of CE place a strong demand on the detection capability. This is especially problematic for absorbance detectors (LOD in the order of 10 to 10 molL ), considered unsuitable for many environmental applications, where trace level occurrence or matrix complexity issues are generally of concern. 

The introduction of capillary columns for GC analysis produced a breakthrough in the analysis of environmental pollutants due to their high separation efficiency. For environmental applications, fused-silica wall-coated open-tubular columns with internal diameters from 0.1 to 0.32 mm and film thickness of 0.1-0.2 pm, and lengths from 25 to 60 m are currently used. The wide range of stationary phases commercially available with different polarities and high thermal stabiHty provides the tool required to maintain the prominent position of GC in environmental analysis. In addition, the availability of chiral stationary phases gives GC the capability to perform GC enantiomer separations. Table 1 gives the recommended columns used in routine analysis of some selected pollutants. 

See also Capillary Electrochromatography. Capillary Electrophoresis Pharmaceutical Applications Low-Mo-lecular-Weight Ions Environmental Applications Food Chemistry Applications Clinical Applications. Electrophoresis Overview. 

See also Capillary Electrochromatography. Capillary Electrophoresis Environmental Applications. Gas Chromatography Overview. Immunoassays Overview. Liquid Chromatography Overview. Mass Spectrometry Overview. Micellar Electrokinetic Chromatography. Sensors Overview. Spectrophotometry Ovenriew. Supercritical Fluid Chromatography Applications. Thin-Layer Chromatography Overview. 

See also Bioassays Overview. Capillary Electrophoresis Overview. Electrophoresis Oven/iew Principles Two-Dimensional Gels. Gas Chromatography Overview Mass Spectrometry. Immunoassays Overview. Immunoassays, Applications Food. Immunoassays, Techniques Radioimmunoassays Enzyme Immunoassays. Liquid Chromatography Reversed Phase Liquid Chromatography-Mass Spectrometry Food Applications. Mass Spectrometry Oven/iew Principles Matrix-Assisted Laser Desorption Ionization Time-of-Flight. Radiochemical Methods Radioreceptor Assays Food and Environmental Applications. Thin-Layer Chromatography Oven/iew. 

C.A. Brinkman, U.A.Th. Environmental applications of large volume injection in capillary GC using PTV injec- 8. 

The growing importance of CE for pesticide-residue analysis is reflected in the publication of the first review articles dealing with the different aspects of its environmental applications [88,170-172]. Table 18.3 shows selected examples of the use of CE for the determination of pesticides. Many involved the use of MEKC for the determination of pesticides in water [85,86,173-181]. CEC, where the mobile phase is transported through a capillary containing a stationary phase with no pressure drop electroosmosis, has also been used for this purpose [171,182,183]. Recently, Wuilloud et al. have developed a method that uses CE and an inductively coupled plasma-mass spectrometric detector for pesticide analysis [184]. 

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