Electron capture gas chromatograph

Rajagopalan et al. [72] described an electron-capture gas chromatographic assay method for the determination of primaquine in blood. The method involves deriva-tization with heptafluorobutyric anhydride to form the diheptafluorobutyramide derivative after a single extraction at alkaline pH. The derivatives are quantitated by electron-capture gas chromatography. Blood levels of primaquine as low as 8 ng/mL can be measured with good precision. 

Aspila et al. [338] reported the results of an interlaboratory quality control study in five laboratories on the electron capture gas chromatographic determination of ten chlorinated insecticides in standards and spiked and unspiked seawater samples (lindane, heptachlor, aldrin, 5-chlordane, a-chlordane, dield-rin, endrin, p, p -DDT, methoxychlor, and mirex). The methods of analyses used by these workers were not discussed, although it is mentioned that the methods were quite similar to those described in the water quality Branch Analytical Methods Manual [339]. Both hexane and benzene were used for the initial extraction of the water samples. 

The electron capture gas chromatographic and ETISA procedures described in section 5.6.1.1 have been applied to the field determination of polychlorobiphenyls in sediments [46]. 

Chen S-H, Wu S-M, Kou H-S, et al. 1994. Electron-capture gas chromatographic determination of cyanide, iodide, nitrite, sulfide and thiocyanate anions by phase-transfer-catalyzed derivatization with pentafluorobenzyl bromide. J Anal Toxicol 18(2) 81-85. 

Moseman RF, Crist HL, Edgerton TR, et al. 1977. Electron capture gas chromatographic... 

Baker GB, Coutts RT, Bornstein RA, Dewhurst WG, Douglass AB, et al. 1986b. An electron-capture gas chromatographic method for analysis of urinary 3-methoxy-4-hydroxyphenylethylene glycol (MHPG). Res Commun Chem Pathol Pharmacol 54 141. 

Baker GB, Rao TS, Coutts RT. 1986a. Electron-capture gas chromatographic analysis of p-phenylethylamine in tissues and body fluids using pentafluorobenzenesulfonyl chloride for derivatization. J Chromatogr Biomed Appl 381 211. 

Paetsch PR, Baker GB, Caffaro LE, Greenshaw AJ, Rauw GA, et al. 1991. An electron-capture gas chromatographic procedure for simultaneous determination of amphetamine and N-methylamphetamine. J Chromatogr Biomed Appl 573 313. 

Rotzinger S, Todd KG, Bourin M, Courts RT, Baker GB. 1997. A rapid electron-capture gas chromatographic method for the quantification of fluvoxamine in brain tissue. J Pharmacol Toxicol Methods 37 129. 

DE Bradway, T Shafik. Electron capture gas chromatographic analysis of the amine metabolites of pesticides derivatization of anilines. J Chromatogr Sci 15 322-328, 1977. 

Deetman et al. [148] have devised an electron capture gas chromatographic technique, applicable to mud samples, for the determination of down to... 

The UK Panel on Fumigant Residues in Grain [58] have developed an electron capture gas chromatographic method for the determination of volatile fumigants such as carbon tetrachloride, chloroform and other chloroaliphatic compounds down to 6 mg/kg of carbon tetrachloride in fumigated wheat, and maize was determined by this method. 

Sereda et al. developed an electron-capture gas chromatographic detection method for the detection of benazepril and other angiotensinconverting enzyme (peptidyl-dipeptidase) inhibitors [26]. Sample solutions (0.001-0.1 mL) containing the inhibitor or metabolite were... 

A two-column electron capture gas chromatographic system, as described under Apparatus, is used for the analysis. Take 5.0-/ liter aliquots of the concentrated extract and inject them into the gas chromatograph. The injections are made on two different types of specially prepared columns, designated as column A and column B (see section on Experimental Results). 

Perhaps the most unfortunate property of the electron capture gas chromatograph is that almost anyone can take one and, after a few hours of instruction from a salesman, can inject samples and obtain recorder responses. This has happened, for there was an immediate rush to get on the band wagon by many workers in various phases of pesticide research and related fields who had absolutely no training in pesticide residue analysis or in the use of instruments such as the gas chromatograph. The result is that there is an unknown, but very substantial, amount of data in the literature that is of absolutely no value and which, more important, may be misleading. It was realized, belatedly by many. 

Buckley KE, Fisher L J, MacKay VG. 1986. Electron capture gas chromatographic determination of traces of formaldehyde in milk as the 2,4-dintrophenylhydrazone. J Assoc Off Anal Chem 69 655-657. 

Fig. 1. Electron capture—gas chromatographic analyses of hexane extracts of a La Jolla, California tidepool at low tide. Trace A is at zero time, the time at which the pool became totally isolated. Trace B is the analysis after 1.5 h and trace C after 3.0 h. The GC conditions were column, 6 X 1/4" 10% DC-200 on Chromosorb Q 80/100 mesh carrier gas 95% argon, 5% methane detector Ni pulse conditions, isothermal at 220°C.

Fig. 2. Electron capture—gas chromatographic analyses of standard pollutants and extracts of several marine organisms A, DDT B, DDE (first peak), DDD C, Laurencia pacifica-, D, Laurencia subopposita E, Chromobacterium sp. F, Arochlor 1242 G, Arochlor 1254 H, Plocamium cartilagineum I, Verongia sp. J, Chondria californica. The GC conditions are identical to those used to produce Fig, 1.

At times the choice of a LLE procedure is aflFected by the type of determinative step. For example, chlorinated solvents are not used with an electron capture gas chromatographic detector. 

Note This class of derivatives is commonly used for electron-capture gas chromatographic analysis. The above two reagents are recommended for derivatizing substances which cannot be conveniently derivatized using perfluoro acid chlorides or anhydrides. 

A Semiautomated Electron Capture Gas Chromatographic Assay of 3-Methoxy-4-hydroxyphenylethyleneglycol in Urine... 

Electron-Capture Gas Chromatographic Determination of Atenolol in Plasma and Urine, Using a Simplified Procedure with Improved Selectivity J. Chromatogr. 162(3-4) 341-347 (1980) CA 93-.88351U... 

A Simple Electron-Capture Gas Chromatographic Analysis of Oxazepam in Plasma by Determination of Its Thermal Degradation Products Can. J. Pharm. Sci. 13(3) 64-65 (1978) CA 90 48125e... 

Simple Electron Capture Gas Chromatographic Method for the Determination of Oral Hypoglycemic Biguanides in Biological Fluids Anal. Chem. 47(3) 545-548 (1975) CA 83 129m... 

Electron-Capture Gas Chromatographic Assay for Metoclopramide in flasma J. Chromatogr. 183(2) 175-184 (1980) CA 93 142548d... 

An Electron-Capture Gas Chromatographic Procedure for the Estimation of Oxalic Acid in Urine Anal. Biochem. 94(2) 470-476 (1979) CA 90 164 69w... 

Improved Method for the Electron-Capture Gas Chromatographic Determination of Trichloroacetic Acid in Human Serum... 

Rapid Sensitive and Specific Electron Capture-Gas Chromatographic Method for the Determination of 6-Chloro-2-(l-piperazinyl)pyrazine in Biological Fluids J. Chromatogr. 162(1) 39-45 (1979) CA 90 80623b... 

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