Simultaneous determination of 45 pesticides in fruit and vegetable using an improved QuEChERS method and on-line gel permeation chromatography–gas chromatography/mass spectrometer

abstract A powerful cleanup procedure for determination of chlorinated pesticides and poly chlorinated biphenyls (PCBs) in difficult agricultural matrixes like feeds or crops was developed to eliminate the interferences in chromatograms obtained by gas chromatography with electron capture detection. The adsorption material used was ENVI-Carb, a graphitized nonporous carbon material. This procedure proved to be more reliable than the established cleanup procedure, which uses gel permeation chromatography and silica gel cartridges. Because ENVI-Carb cleanup delivers clear, colorless eluates with no interferences, chlorinated pesticides and PCBs may be detected at levels as low as 0.0004 mg/kg for monitoring purposes. Accuracy was validated through a series of recovery experiments.

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Determination of iV-Methylcarbamate Pesticides in Liver by Liquid Chromatography

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/72.4.586 ◽

1989 ◽

Vol 72 (4) ◽

pp. 586-592 ◽

Cited By ~ 3

Author(s):

Sher M Ali

Keyword(s):

Liquid Chromatography ◽

Simultaneous Determination ◽

Fluorescence Detection ◽

Methylene Chloride ◽

Gel Permeation Chromatography ◽

Purification Technique ◽

Coefficients Of Variation ◽

Gel Permeation ◽

Liquid Chromatographic

Abstract A liquid chromatographic (LC) method using a 2-step purification technique for the simultaneous determination of 10 carbamates in bovine, swine, and duck livers has been developed. Carbamates are extracted from liver samples with methylene chloride. After evaporation, the residues from the extract are dissolved in methylene chloride- cyclohexane (1 + 1) and cleaned up by gel permeation chromatography. The eluate containing carbamate residues is evaporated to dryness, reconstituted in methylene chloride, further purified by passing it through an aminopropyl Bond Elut extraction cartridge, and analyzed by liquid chromatography using post-column derivatization with orthophthalaldehyde and fluorescence detection. Excitation and emission are set at 340 and 418 nm, respectively. Liver samples for beef, pork, and duck were fortified with 5, 10, and 20 ppb of mixed carbamate standards. The average of 10 recoveries of 10 carbamates at all 3 levels of fortification was greater than 80% with coefficients of variation less than 17%.

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A highly automated method for simultaneous determination of sterols, erythrodiol and uvaol in olive oils

Analytical Methods ◽

10.1039/c6ay00357e ◽

2016 ◽

Vol 8 (20) ◽

pp. 4022-4027 ◽

Cited By ~ 5

Author(s):

Qiang Gu ◽

Xiaojuan Yi ◽

Jinling Shen ◽

Jing Shi ◽

Yijun Liu ◽

...

Keyword(s):

Simultaneous Determination ◽

Gel Permeation Chromatography ◽

Simultaneous Analysis ◽

Olive Oils ◽

Automated Method ◽

Gel Permeation ◽

Erythrodiol And Uvaol

In this work, we presented a highly automated method for the simultaneous analysis of sterols, erythrodiol and uvaol in olive oils with the use of gel permeation chromatography (GPC), an automatic solvent evaporator and LC-MS.

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