Electron capture detection for

Duinker, J.C., D.E. Schulz, and G. Petrik. 1988b. Multidimensional gas chromatography with electron capture detection for the determination of toxic congeners in polychlorinated biphenyl mixtures. Anal. Chem. 60 478-482. 

Angerer J, Kafferlein HU (1997) Gas chromatographic method using electron-capture detection for the determination of musk xylene in human blood samples. J Chromatogr B 693 71-78... 

The inherent insensitivity of these methods prompted an evaluation of gas-liquid chromatography with electron capture detection for the analysis of TRIS. Due to the... 

Mierzwa, S. and Witek, S., Gas-liquid chromatographic method with electron-capture detection for the determination of residues of some phenoxyacetic acid herbicides in water as their 2,2-trichloroethyl esters, J. Chromatogr., 136, 105, 1977. 

I. Martin, G. Baker, et al., Gas chromatography with electron capture detection for measurement of bioactive amines in biological samples, Methodol. Surv. Biochem. Anal., 74 331-336 (1984). 

For the determination of nitrate, use a 1 dram vial with a polyethylene stopper (Kimble No. 60975-L) as a reaction vessel. Introduce a 0.20ml aliquot of aqueous sample into the vial, followed by 1.0ml of thiophen free benzene. Catalyse the reaction by addition of 1.0ml of concentrated sulphuric acid. Shake the vial for lOmin. Remove the benzene layer immediately from the reaction vial with a Pasteur pipette, place it in a separate vial and analyse by gas chromatography with electron capture detection for the nitrobenzene concentration generated. Treat standard solutions of potassium nitrate in the same manner to generate a standard calibration plot relating nitrobenzene concentration to peak height. If higher precision is desired (approximately 4% relative standard deviation), add 2,5-dimethylnitrobenzene to the benzene prior to reaction. 

As stated above, most users of the headspace technique make no distinction between dynamic HS and PT. In one of the few publications that distinguished and compared these two HS modes, dynamic HS and PT were assessed as steps preceding high-resolution GC-electron capture detection for the determination of nitrous oxide in sea water. The process was found to exhibit a first-order kinetics in both cases and the matrix to exert a significant effect that was proportional to the nitrous oxide concentration in bidistilled water, as well as in synthetic and natural sea water. As expected, PT provided better extraction recovery, sensitivity and limits of detection — which fell in the pico-mole-per-millilitre range [46]. 

Jalali-Heravi, M., Noroozian, E. and Mousavi, M. (2004) Prediction of relative response factors of electron-capture detection for some polychlorinated biphenyls using chemometrics. 

A lot of interest in catecholamine metabolism has centred on their metabolic end-products 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) and 3-methoxy-4-hydroxyphenylethanol (MHPE). These compounds have been analysed most often as their TFA or PFP derivatives, with electron capture detection for sensitivity. Many different recipes have been published, all variants of the anhydride in ethyl acetate procedure, using different temperatures and reaction times. If 30 minutes at room temperature are sufficient [94], one does not need 40 minutes at 65 °C [95]. Pyridine is not recommended because it gives rise to interference, just as with acetic anhydride (see above). At the end of the reaction the mixture is evaporated to dryness with nitrogen, and the residue is taken up in ethyl acetate. These derivatives are susceptible to hydrolysis, and up to 2% of acetic anhydride may be included in the final solution to protect the derivatives against moisture. 

A Method of Gas Chromatography Using Electron-Capture Detection for the Determination of Blood Concentrations of Halothane, Chloroform and Trichloroethylene... 

Online sorptive preconcentration exploiting renewable solid surfaces, the so-called bead injection (Bl), in the miniaturized LOV platform has been hyphenated to GC separation with electron-capture detection for automated determination of trace levels of PCBs in solid-waste leachates. To this end, the MSFIA system presented in Chapter 3, Figure 3.19, has been implemented. It comprises a mul-tisyringe burette, an extra solenoid valve, an LOV, and an injection valve (IV) as well as reversed-phase copolymeric beads with hydroxylated surface (Bond Elut Plexa) included into the channels of a poly(ether imide) LOV microconduit, thus serving as a transient microcolumn-packed reactor for preconcentration of organic species [194]. 

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