Chemical Assay of Chick Edema Factor in Fats and Fatty Acids

1964 ◽  
Vol 47 (4) ◽  
pp. 772-776
Author(s):  
G R Higginbotham
Keyword(s):  
Gas Chromatography ◽  
Electron Capture ◽  
Chromatographic Method ◽  
Activated Alumina ◽  
Alumina Column ◽  
The Third ◽  
Edema Factor ◽  
Chemical Assay ◽  
Cleanup Procedure ◽  
Gas Chromatographic Method

Abstract A microcoulometric gas chromatographic method for detecting chick edema factor in fats was studied collaboratively by six laboratories. The method involved extracting unsaponifiable material from fat and fractionating it on an activated alumina column, then examining the third alumina fraction by microcoulometric gas chromatography. Results did not warrant adoption of the method. Initial studies with electron capture gas chromatography for this determination showed promise. A better cleanup procedure needs to be developed. It is planned to continue the study, and to combine acetonitrile extraction and cleanup on an acid- Celite column with electron capture determination.

Detection of Chick Edema Factor in Fats and Fatty Acids by Electron Capture Gas Chromatography

1967 ◽  
Vol 50 (4) ◽  
pp. 874-879
Author(s):  
G R Higginbotham ◽  
David Firestone ◽  
Linda Chavez ◽  
A D Campbell
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Screening Test ◽  
Alumina Column ◽  
The Third ◽  
Edema Factor ◽  
Collaborative Studies ◽  
Alumina Column Chromatography ◽  
Chromatographic Peaks

Abstract An electron capture gas chromatographic screening test has been developed for detecting chick edema factor in fats and fatty acids. The procedure involves extraction of unsaponifiables from 10 g fat, alumina column chromatography of the unsaponifiables, sulfuric acid cleanup of the third alumina fraction (25% ethyl ether in petroleum ether), and electron capture gas chromatography at 200°C. Gas chromatographic peaks with retention times vs. aldrin between 10 and 25 are indicative of thepresence of chick edema factor. The screening test has been evaluated by two collaborative studies, and results indicate that the method is suitable as a screening test for chick edema factor.

Gas Chromatographic Determination of N-Butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-toluidine and α,α,α-Trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine in Formulations

1971 ◽  
Vol 54 (3) ◽  
pp. 711-712
Author(s):  
Martha Fuzesi
Keyword(s):  
Gas Chromatography ◽  
Quantitative Determination ◽  
Electron Capture ◽  
Chromatographic Method ◽  
Chromatographic Determination ◽  
Electron Capture Detector ◽  
Reference Solution ◽  
Gas Chromatographic Method

Abstract A gas chromatographic method is described for the quantitative determination of N-butyl-N-ethyl-α,α,α-trifluoro-2,6-dinitro-p-tolindine and α,α,α-trifluoro-2,6-dinitro-N,N-dipropyI-p-toluidine herbicides in formulations. The sample is extracted with benzene, and equal amounts of sample and reference solution in the same concentration range are analyzed by gas chromatography, using an electron capture detector and an SE-30/Diatoport S column. The method has been applied successfully to laboratory-prepared and commercial samples.

Determination of fluoxetine and norfluoxetine in plasma by gas chromatography with electron-capture detection.

1982 ◽  
Vol 28 (10) ◽  
pp. 2100-2102 ◽  
Author(s):  
J F Nash ◽  
R J Bopp ◽  
R H Carmichael ◽  
K Z Farid ◽  
L Lemberger
Keyword(s):  
Gas Chromatography ◽  
Human Plasma ◽  
Electron Capture ◽  
Relative Error ◽  
Chromatographic Method ◽  
Linear Range ◽  
Electron Capture Detector ◽  
Electron Capture Detection ◽  
Gas Chromatographic Method

Abstract This gas-chromatographic method for assay of fluoxetine and norfluoxetine in human plasma involves extraction of the drugs and use of a 63Ni electron-capture detector. The linear range of detection is 25 to 800 micrograms/L for each drug. Overall precision (CV) in the concentration range of 10 to 100 micrograms/L for both drugs was approximately 10%. Accuracy (relative error) in the same concentration range was approximately +10%. None of the commonly prescribed antidepressants or tranquilizers that we tested interfere with the assay.

Analysis of Total Free and Glucose-Conjugated Pyrethroid Acid Metabolites in Tea Infusions as Hexafluoroisopropyl Esters by Gas Chromatography with Electron Capture Detection

1995 ◽  
Vol 78 (3) ◽  
pp. 846-855 ◽  
Author(s):  
Richard D Mortimer ◽  
Dorcas F Weber ◽  
Wing F Sun
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Chromatographic Method ◽  
Electron Capture Detection ◽  
Tea Leaves ◽  
Tea Infusions ◽  
Acid Metabolites ◽  
Pyrethroid Metabolites ◽  
Gas Chromatographic Method

Abstract A gas chromatographic method with electron capture detection (GC–ECD) has been developed to quantitate the sum of free acids of pyrethroid metabolites, their glucosides, and their other base-cleav-able conjugates that are extracted from tea leaves when a tea infusion is prepared. Four representative glucoside conjugates were synthesized; hydrolytic conditions were established; and extraction, derivatization and GC conditions were developed for analysis of these pyrethroid acid metabolites at ≥0.01 ppm on dry tea. GC/mass spectrometry was used to confirm assignment of residues found in some tea samples.

Detection of Chick Edema Factor and Other Chlorinated Hydrocarbons in Fats and Oils by Electron Capture Gas Chromatography: Use of TLC as a Preliminary Cleanup Procedure

1967 ◽  
Vol 50 (1) ◽  
pp. 16-21
Author(s):  
Anita Huang ◽  
David Firestone ◽  
A D Campbell
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Acid Treatment ◽  
Fats And Oils ◽  
Sulfuric Acid Treatment ◽  
Edema Factor ◽  
Cleanup Procedure ◽  
Chromatographic Procedure ◽  
Specific Fraction

Abstract A thin layer chromatographic (TLC) procedure is described for detecting chick edema factor in fats and oils. A specific fraction containing chick edema factor compounds is isolated by TLC from extracted unsaponifiables and cleaned up by sulfuric acid treatment. The residue is analyzed by electron capture gas chromatography. Results on several toxic samples of fats or fatty acids were comparable to the alumina adsorption column-electron capture gas chromatographic procedure. A 1.56% reference toxic fat sample can be detected under the conditions described. Toxicity of the specific TLC fraction was verified by tissue culture and chick embryo assay. Highly chlorinated biphenyls and naphthalenes which produce characteristic symptoms of chick edema disease at higher levels than the chick edema factor were also detected.

Extraction and Cleanup Procedure for the Gas Chromatographic Determination of Four Dinitrophenolic Pesticides

1968 ◽  
Vol 51 (1) ◽  
pp. 24-28
Author(s):  
George Yip ◽  
Samuel F Howard
Keyword(s):  
Simultaneous Determination ◽  
Electron Capture ◽  
Methyl Ether ◽  
Chromatographic Method ◽  
Chromatographic Determination ◽  
Green Beans ◽  
Cleanup Procedure ◽  
Lima Beans ◽  
Gas Chromatographic Method

Abstract A gas chromatographic method for the simultaneous determination of four dinitrophenolic herbicides [dinitrocresol (DNOC), dinitrobutylphenol (DNBP), dinitroamylphenol (DNAP), and dinitrocyclohexylphenol (DNOCHP)] in crops has been developed. After a 50 g sample was extracted with chloroform, a 10 g aliquot was concentrated and reacted with diazomethane to form the methyl ether derivatives. The sample was subjected to a two column cleanup step. acid-Celite and Florisil, and the residue was analyzed by GLC with an electron capture detector. Recoveries of fortification levels of 0.1 ppm DNOC and 0.2 ppm DNBP, DNAP, and DNOCHP exceeded 80%. The crops studied included green beans, pole beans, lima beans, peas, apples, and oranges.

Evaluation of Electron Capture Gas Chromatographic Method for Determination of Methyl Mercury in Freezer-Case Seafoods

1984 ◽  
Vol 67 (4) ◽  
pp. 715-717
Author(s):  
George H Alvarez ◽  
George H Hight ◽  
Stephen G Capar
Keyword(s):  
Gas Chromatography ◽  
Electron Capture ◽  
Mercuric Chloride ◽  
Methyl Mercury ◽  
Chloride Solution ◽  
Chromatographic Method ◽  
Mercuric Chloride Solution ◽  
Fresh Frozen ◽  
Gas Chromatographic Method

Abstract A method was recently adopted by AOAC for determination of methylbound mercury in canned and fresh-frozen seafood by electron capture gas chromatography. That method was applied to the analysis of commercially prepared freezer-case seafoods. None of the commercially added ingredients produced electron capture responses that interfered in the analysis for methyl mercury. Recoveries of 95.7-114% were obtained in fortification studies of methyl mercury at 0.2 and 1.0 ppm levels. The applicability of aqueous methyl mercuric chloride solution for fortification studies was demonstrated.

Determination of DDVP in DDVP-Dipterex Formulations by Gas Chromatography

1965 ◽  
Vol 48 (6) ◽  
pp. 1115-1117
Author(s):  
John Ellis ◽  
John Bates
Keyword(s):  
Gas Chromatography ◽  
Electron Capture ◽  
Chromatographic Method ◽  
Spectrophotometric Methods ◽  
Other Substances ◽  
Gas Chromatographic Method

Abstract In the analyses of commercial fly-bait samples for DDVP (0,0-dimethyI-2,2-dichloro vinyl phosphate), containing Dipterex (0,0-dimethyl-2,2,2-trichloro - 1 - hydroxyethyl phosphonate) as a guaranteed ingredient, interferences were observed at 9.9– 10.4/t with the current spectrophotometric methods. These samples were analyzed by an electron capture gas chromatographic method, and the results showed no interference from Dipterex or other substances. A selected group of samples was analyzed by gas chromatography and spectrophotometry, and the results were compared.

The Importance of Alcohol Testing by Gas Chromatography vs the Cordebard Classical Method Modified in the Medico Legal Investigation

2018 ◽  
Vol 69 (9) ◽  
pp. 2407-2410
Author(s):  
Dan Perju Dumbrava ◽  
Carmen Corina Radu ◽  
Sofia David ◽  
Tatiana Iov ◽  
Catalin Jan Iov ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Chromatographic Method ◽  
Classical Method ◽  
Blood Alcohol Concentration ◽  
Alcohol Concentration ◽  
Blood Alcohol ◽  
Technical Details ◽  
Gas Chromatographic Method ◽  
Alcohol Testing ◽  
Living Person

Considering the growing number of requests from the criminal investigations authorities addressed to the institutions of legal medicine, testing of blood alcohol concentration both in the living person and in the corpse, we believe that a presentation of the two methods which are used in our country, is a topic of interest at present. The purpose of this article is to provide the reader with the technical details on how blodd alcohol concentration is realised by means of the gas chromatographic method and the classical one, (Cordebard modified by D. Banciu and I. Droc) respectively. Another purpose of this article is to also show, in a comparative way, the elements that make the gas chromatographic method superior to the former one.

Antioxidants (BHA and BHT) in Breakfast Cereals

1965 ◽  
Vol 48 (4) ◽  
pp. 694-699
Author(s):  
David M Takahashi
Keyword(s):  
Gas Chromatography ◽  
Petroleum Ether ◽  
Chromatographic Method ◽  
Steam Distillation ◽  
Gas Chromatograph ◽  
Breakfast Cereals ◽  
Collaborative Studies ◽  
Different Types ◽  
Gas Chromatographic Method

Abstract Antioxidants (BHA and BHT) in different types of breakfast cereals were studied by argon ionization gas chromatography. Samples containing antioxidants were packed into the column, and antioxidants were eluted with redistilled petroleum ether. EIuates were concentrated under N2 and injected into a Barber-Colman Model 10 gas chromatograph. Recoveries ranged from about 92 to 110%. Results obtained by steam distillation-colorimetry methods were erratic. Colorimetric procedures were not free from interferences and could lead to highly erroneous results at the lower ppm levels. The gas chromatographic method is faster, simpler, and more accurate. Collaborative studies on corn and rice ready-to-eat breakfast cereals are recommended.

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