Improved Multiresidue Gas Chromatographic Determination of Organophosphorus, Organonitrogen, and Organohalogen Pesticides in Produce, Using Flame Photometric and Electrolytic Conductivity Detectors

1981 ◽  
Vol 64 (5) ◽  
pp. 1187-1195 ◽  
Author(s):  
Milton A Luke ◽  
Jerry E Froberg ◽  
Gregory M Doose ◽  
Herbert T Masumoto
Keyword(s):  
Petroleum Ether ◽  
Methylene Chloride ◽  
Organophosphorus Pesticides ◽  
Chromatographic Determination ◽  
Electrolytic Conductivity ◽  
Gas Chromatograph ◽  
Flame Photometric Detector ◽  
Initial Concentration ◽  
Photometric Detector

Abstract The multiresidue procedure of Luke et al., which uses extraction with acetone and partition with petroleum ether and methylene chloride, was simplified and shortened by eliminating the Florisil cleanup. Double concentration with petroleum ether in the Kuderna-Danish evaporator following the initial concentration removed the last traces of methylene chloride. The extract was then injected into a gas chromatograph, using a Hall electrolytic conductivity detector for organohalogen, organonitrogen, and organosulfur pesticides or a flame photometric detector for organophosphorus pesticides. Recoveries of 79 pesticides are presented.

A Rapid Specific Method for the Gas Chromatographic Determination of Organophosphate Pesticides in Cold Pressed Citrus Oils

1967 ◽  
Vol 50 (6) ◽  
pp. 1236-1242
Author(s):  
Robert K Stevens
Keyword(s):  
Analytical Procedure ◽  
Chromatographic Determination ◽  
Specific Method ◽  
Organophosphate Pesticides ◽  
Gas Chromatograph ◽  
Flame Photometric Detector ◽  
Photometric Detector ◽  
Cold Pressed

Abstract Organophosphate pesticides in cold pressed citrus oils can be determined rapidly by a method using gas chromatographic procedures and the flame photometric detector developed by Brody and Chaney. This study revealed that cold pressed citrus oils obtained from the 1965— 1966 citrus crops from Florida and California contained from 1.5 to 20 ppm thiophosphate pesticides. The analytical procedure required approximately 40 min per analysis and eliminated the need for extensive preparation of the sample prior to introduction into the gas chromatograph. The procedure is more specific and less time consuming than methods previously described

Gas Chromatographic Determination of Ametryn and Its Metabolites in Tropical Root Crops

1984 ◽  
Vol 67 (2) ◽  
pp. 280-284
Author(s):  
Promode C Bardalaye ◽  
Willis B Wheeler
Keyword(s):  
Anhydrous Sodium Sulfate ◽  
Residue Analysis ◽  
Gel Permeation Chromatography ◽  
Chromatographic Determination ◽  
Solvent System ◽  
Complete Separation ◽  
Flame Photometric Detector ◽  
Root Crops ◽  
Photometric Detector

Abstract Residue analysis of the herbicide ametryn (2-methyIthio-4-ethylamino-s-isopropylamino-s-triazine) is widely known but an analytical method for determining its metabolites has not yet been reported in the literature. A method has been developed for the extraction and determination of ametryn and 3 metabolites, 2-methylthio-4-amino-6-isopropylammo- s-triazine (GS-11354), 2-methylthio-4,6-diamino-.s-triazine(GS- 26831), and 2-methylthio-4-amino-6-ethylamino-s-triazine (GS-11355) in taniers, yams, cassava. Residues were extracted from crops with ethyl acetate-toluene (3 + 1 v/v), using a Polytron homogenizer and anhydrous sodium sulfate added for drying. The extracts were cleaned up by automated gel permeation chromatography on Bio-Beads SX-3 gel in the same solvent system. Quantitative determination was performed by gas chromatographic (GC) analysis on a column packed with 5% DEGS-PS on 100-120 mesh Supelcoport using either an N-P detector or a flame photometric detector (FPD) in the sulfur mode. Minimum detection by the flame photometric detector is 10 ng each for ametryn, GS-11354, and GS-11355 and 21 ng for GS-26831; by the N-P detector, 0.3 ng of each component gives easily quantitatable peaks. On a parts per million basis, starting with 25 g sample, the FPD detected a minimum level of 0.04 p.g/g each for ametryn, GS-11354, and GS-11355, and 0.08 p.g/g for GS-26831. The N-P detector could detect 0.0024 p.g/g for all 4 compounds. In addition to superior sensitivity, instrumental conditions allowed the complete separation of components in 10 min, for the N-P detector; more than 30 min was required for the FPD. Recoveries from fortified crops ranged from 67 to 111% at levels of 0.1-1.0 μg/g.

Collaborative Study of a Gas Chromatographic Determination of Methylene Chloride, Ethylene Dichloride, and Trichloroethylene Residues in Spice Oleoresins

1968 ◽  
Vol 51 (4) ◽  
pp. 825-828
Author(s):  
Laura A Roberts
Keyword(s):  
Methylene Chloride ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Chromatographic Column ◽  
Ethylene Dichloride ◽  
Gas Chromatograph ◽  
Porapak Q ◽  
Relative Retention ◽  
Solvent Residues

Abstract A method for the gas chromatographic determination of methylene chloride, ethylene dichloride, and trichloroethylene residues in spice oleoresins was studied collaboratively. The method employs a microcoulometric gas chromatograph fitted with a Porapak Q column and is based on the volatility of the solvent residues, their relative retention times on a polyaromatic bead chromatographic column, and their detectability by a halide-specific microcoulometric method. Recoveries were adequate when the method was closely followed; recoveries were erratic when collaborators deviated from the method. Further study is recommended.

scholarly journals Determination of sulfuric acid particles in the atmosphere by a gas chromatograph with flame photometric detector.

1986 ◽  
pp. 100-104
Author(s):  
Toshiro MATSUMURA ◽  
Katsuaki KAMETANI ◽  
Hitoshi TODORIKI ◽  
Tadanori TAKEMURA ◽  
Mariko TODOME ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Gas Chromatograph ◽  
Flame Photometric Detector ◽  
Photometric Detector

Gas Chromatographic Determination of Metribuzin in Formulations: Collaborative Study

1984 ◽  
Vol 67 (4) ◽  
pp. 840-843
Author(s):  
William R Betker ◽  
◽  
D Anderson ◽  
J M Bajovich ◽  
O O Bennett ◽  
...  
Keyword(s):  
Methylene Chloride ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Peak Height ◽  
Gas Chromatograph ◽  
Significant Difference ◽  
Butyl Phthalate ◽  
Gas Chromatographic Method

Abstract A collaborative study was conducted on a gas chromatographic method for determining metribuzin. Two 75% dry flow able and two 42% liquid flowable formulations were analyzed by 18 laboratories. Formulations were extracted by shaking or ultrasonic mixing for 1-5 min with methylene chloride which contained di-n-butyl phthalate as an internal standard. The extracts were injected into a gas chromatograph equipped with an OV-225 column. Peak area ratios and peak height ratios showed no significant difference. The reproducibility coefficient of variation was 0.75% for the 75% formulation and 1.41% for the 42% formulation. This GC method has been adopted official first action.

Gas Chromatographic Determination of Ethylene Thiourea Residues

1973 ◽  
Vol 56 (2) ◽  
pp. 333-337 ◽  
Author(s):  
Linwood D Haines ◽  
Irving L Adler
Keyword(s):  
Gas Chromatography ◽  
Sodium Borohydride ◽  
Chromatographic Determination ◽  
Food Crops ◽  
Alumina Column ◽  
Flame Photometric Detector ◽  
Photometric Detector ◽  
Ethylene Thiourea

Abstract Residues of ethylene thiourea on food crops are determined by extracting the sample with methanol, partially purifying the extract on an alumina column, and derivatizing the ethylene thiourea extracted with 1-bromobutane in the presence of dimethylformamide and sodium borohydride. The resulting derivative is measured by gas chromatography, using a flame photometric detector. The method is suitable for routine use and is sensitive to 0.01 ppm.

Gas Chromatographic Determination of Fensulfothion in Formulations: Collaborative Study

1986 ◽  
Vol 69 (3) ◽  
pp. 488-490
Author(s):  
William R Betker ◽  
◽  
E W Balcer ◽  
O O Bennett ◽  
W R Coffman ◽  
...  
Keyword(s):  
Chromatographic Method ◽  
Methylene Chloride ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Gas Chromatograph ◽  
Technical Product ◽  
Coefficients Of Variation ◽  
Gas Chromatographic Method

Abstract A collaborative study was conducted on a gas chromatographic method for determination of fensulfothion. Eleven laboratories analyzed 2 technical and two 6 lb/U.S. gal. spray concentrate samples. In the analysis, samples are dissolved in methylene chloride which contains 4-chlorophenyl sulfoxide as an internal standard, and solutions are injected into a gas chromatograph equipped with an OV-330 column. Withinlaboratory repeatability was 0.79% for technical product and 0.37% for the spray concentrate samples, with coefficients of variation of 0.88 and 0.58%, respectively. Among-laboratories reproducibility was 0.81% for technical product and 0.53% for the spray concentrate, with coefficients of variation of 0.91 and 0.84%, respectively. The method has been adopted official first action.

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