Chromatographic determination of carbon monoxide below the 1 ppm level

Abstract An interlaboratory study of the determination of captan, folpet, and captafol in tomatoes, cucumbers, and apples was conducted by 4 laboratories using wide-bore capillary column gas chromatography with electron capture detection. The 3 fungicides were determined using the Luke et al. multlresidue method modified to Include additional solvent elutlon in the optional Florisll column cleanup step used with this method. The crops were fortified with each fungicide at 3 levels per crop. Mean recoveries ranged from 86.2% for a 25.1 ppm level of captan in apples to 115.4% for a 0.288 ppm level of captafol In apples. Interlaboratory coefficients of variation ranged from 3.4% (24.7 ppm folpet) to 9.7% (0.243 ppm captafol) for tomatoes; from 2.8% (2.0 ppm captafol) to 8.2% (24.8 ppm captan) for cucumbers; and from 1.5% (0.234 ppm folpet) to 22.1% (0.266 ppm captafol) for apples.

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Semiautomated Liquid Chromatographic Determination of Clopidol in Poultry Feed

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.3.551 ◽

1971 ◽

Vol 54 (3) ◽

pp. 551-554 ◽

Cited By ~ 1

Author(s):

N E Skelly ◽

R F Cornier

Keyword(s):

Ion Exchange ◽

Methanol Extract ◽

Chromatographic Determination ◽

Poultry Feed ◽

Alumina Column ◽

Accuracy And Precision ◽

Liquid Chromatographic Determination ◽

Liquid Chromatographic ◽

Ppm Level

Abstract A semiautomated ion exchange-ultraviolet procedure has been developed for the determination of clopidol in poultry feed at the 40–250 ppm level. A methanol extract of the feed is injected into an alumina precolumn to remove interferences. The clopidol passes through the alumina column and is collected on an ion exchange column. With a specially designed elution apparatus the clopidol is removed by an acetic acid-methanol gradient. The eluate proceeds through a flowcell mounted in an ultraviolet spectrophotometer. Response of the spectrophotometer is monitored by a recorder. Concentration is determined by comparing the peak area in the resulting chromatogram with that of a standard. Accuracy and precision of this method are ±5% relative to the amount present (100±5 ppm).

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Improved Gas Chromatographic Method for Determination of Daminozide by Alkaline Hydrolysis and 2-Nitrobenzaldehyde Derivatization and Survey Results of Daminozide in Agricultural Products

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/73.4.512 ◽

1990 ◽

Vol 73 (4) ◽

pp. 512-515

Author(s):

Kurt Steinbrecher ◽

Wilbur L Saxton ◽

George A Oehler

Keyword(s):

Alkaline Hydrolysis ◽

Chromatographic Determination ◽

Detectable Level ◽

Agricultural Products ◽

Improved Method ◽

Two Samples ◽

Survey Results ◽

Gas Chromatographic Method ◽

Ppm Level

Abstract An improved method was developed for the quantitative determination of daminozide. This new method combines the alkaline hydrolysis and distillation steps of the PAMII method for daminozide with the derivatization, cleanup, and gas chromatographic determination steps of the Wright method for unsymmetrlcal dimethyl hydrazine (UDMH). The minimum detectable level Is 0.05 ppm. Recoveries range from 85 to 110% when daminozide Is added at 0.1 to 1.0 ppm, and are generally 40% at the 0.05 ppm level. A variety of domestic and imported products were analyzed by this Improved method and daminozide was detected In 33 of the 98 samples analyzed. Levels detected ranged from a trace amount to 0.80 ppm. The Identity of UDMH hydrazone was confirmed by mass spectrometry In many samples, thus confirming the presence of daminozide. Two samples containing daminozide were analyzed Independently by a second laboratory and the findings were closely duplicated.

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Thin Layer Chromatographic Detection and Indirect Gas Chromatographic Determination of Three Carbamate Pesticides

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/58.5.1015 ◽

1975 ◽

Vol 58 (5) ◽

pp. 1015-1019

Author(s):

George F Ernst ◽

Saskia J Röder ◽

Gwan H Tjan ◽

John T A Jansen

Keyword(s):

Methylene Chloride ◽

Chromatographic Determination ◽

Carbamate Pesticides ◽

Chromatographic Detection ◽

Vegetables And Fruits ◽

Phenyl Ethers ◽

Ppm Level ◽

Inhibition Technique ◽

Carbamate Pesticide

Abstract Carbamate pesticide residues are extracted from vegetables and fruits with methylene chloride. The extracts are spotted on silica gel plates and the pesticides are detected by an enzymatic inhibition technique. For quantitative determination, aliquots of the methylene chloride extracts are evaporated to dryness in a rotary evaporator. After the residues are dissolved in ethanol, 0.5N NaOH is added in the hydrolysis step. To remove a number of possible interferences the hydrolyzed phenols are steamdistilled and treated with l-fluoro-2, t-dinitrobenzene and/or 4-chloro-α,α,α-trifluoro-3,5-dinitrotoluene to form the ether derivatives. Efficiency in the conversion of the phenolic moieties to the phenyl ethers is about 100%. The resulting electron-capturing derivatives enable the carbamate pesticides to be detected in vegetables and fruits at the 0.05 ppm level. Recoveries of 90–94% were obtained from vegetables and fruits fortified with 0.5–2.0 ppm carbaryl, Mesurol, and propoxur.

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Gas-Liquid Chromatographic Determination of Chlorinated Norbornene Derivatives in Fish

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/61.1.26 ◽

1978 ◽

Vol 61 (1) ◽

pp. 26-31

Author(s):

Martin P Yurawecz ◽

John A G Roach

Keyword(s):

Petroleum Ether ◽

Mississippi River ◽

Chromatographic Determination ◽

Gas Liquid Chromatography ◽

Chlorinated Pesticides ◽

Liquid Chromatographic Determination ◽

Liquid Chromatographic ◽

Norbornene Derivatives ◽

Ppm Level

Abstract 1,2,3,4,7,7 - Hexachloro - 2,5 - norbornadiene (I), 1,2,3,4,5 - endo,7,7 - heptachloro - 2 - norbornene (II), and l,2,3,4,7,7-hexachloro-5,6-erecfoepoxy- 2-norbornene (III) have been identified as contaminants in Mississippi River fish by combined gas-liquid chromatography (GLC)- mass spectrometry. The method used to determine residues of these compounds, which are associated with production of the pesticide endrin, is similar to the AOAC multiresidue method for chlorinated pesticides. The residues are extracted from the sample with acetonitrile, transferred to petroleum ether, and chromatographed on a Florisil column. Compounds I and II are eluted from the Florisil with petroleum ether and compound III is eluted with ethyl ether-petroleum ether (6+94). The concentrated eluates are analyzed by using electron capture GLC. The method provides adequate recoveries of all 3 chlorinated norbornene derivatives and allows quantitation at or below the 0.05 ppm level in fish with a 20 mg sample equivalent injection.

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Capillary Gas Chromatographic Determination with Electron Capture Detector of β-Propiolactone in Biological Materials

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/74.4.595 ◽

1991 ◽

Vol 74 (4) ◽

pp. 595-599

Author(s):

Aziz Geahchan ◽

Bruno Fouillet ◽

Paul Chambon ◽

Renee Chambon ◽

Bahia Nouri

Keyword(s):

Electron Capture ◽

Limit Of Detection ◽

Chromatographic Determination ◽

Biological Materials ◽

Electron Capture Detector ◽

Detector Response ◽

Limit Of Quantitation ◽

Low Levels ◽

Ppm Level

Abstract A method has been developed for the determination of β- propiolactone by derivatizing it to the volatile N-hexyl-3- heptafluorobutanoyloxypropanamide, which can be separated and Identified by a capillary CP-Sil 8 column, and detected by an electron capture detector (ECD). First, β- propiolactone is reacted with N-hexylamine to yield N-hexyl- 3-hydroxypropanamide. The fluorobutanoyl ester derivative is next prepared by using heptafluorobutyrlc acid anhydride in the presence of trimethylamine. The method Is very sensitive, simple, and specific, and can be used to detect and quantitate residual β-propiolactone In Iyophilized biological materials. The limit of detection is 0.2 ppm β-proplolactone in a 50 mg sample; however, because of variability at low levels, the limit of quantitation is 1 ppm. Detector response was linear for 2-500 ng β-propiolactone. Recoveries were 98% or greater from Iyophilized vaccines spiked at the 2-20 ppm level. No side products or interference peaks were observed in the derivatization reaction.

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Gas-Solid Chromatographic Determination of Carbon Monoxide and Carbon Dioxide in Cigarette Smoke

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/57.1.1 ◽

1974 ◽

Vol 57 (1) ◽

pp. 1-7

Author(s):

Arthur D Horton ◽

Michael R Guerin

Keyword(s):

Carbon Dioxide ◽

Carbon Monoxide ◽

Gas Phase ◽

Confidence Intervals ◽

Cigarette Smoke ◽

Chromatographic Determination ◽

Standard Errors ◽

Sampling Techniques ◽

Relative Standard

Abstract Gas-solid chromatographic methods are presented for the determination of carbon monoxide, carbon dioxide, or both simultaneously in the gas phase of cigarette smoke. The methods are optimized to allow quantitative determinations on the entire gas phase delivery of the cigarettes rather than single puffs and to allow the use of small numbers of cigarettes. Shortcomings of several sampling techniques are defined, and evidence is presented supporting the utility of Saran bag sampling and containment. Carbon monoxide and carbon dioxide analyses may be performed with relative standard errors of 2—3% and relative confidence intervals (95%) of 6—9% for determinations involving 4—6 cigarettes.

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