Comparison of Some Cleanup Columns for Residue Analysis of Chlorinated and Phosphorus-Containing Pesticides

Abstract A comparison is presented of 8 of the most widely used cleanup methods based on adsorption column chromatography for chlorinated and phosphorus-containing compounds and their metabolites. For chlorinated pesticides, all methods show equivalent efficiency and recovery. For phosphorus-containing compounds and metabolites, methods employing columns filled with adsorbent mixtures work better than “all-Florisii” columns.

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A Sweep Co-distillation Cleanup Method for Organophosphate Pesticides.

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/48.6.1154 ◽

1965 ◽

Vol 48 (6) ◽

pp. 1154-1158

Author(s):

R W Storherr ◽

R R Watts

Keyword(s):

Column Chromatography ◽

Pesticide Residues ◽

Methyl Parathion ◽

Organophosphate Pesticides ◽

Organophosphate Pesticide ◽

Distillation Method ◽

Adsorption Column ◽

Column Method ◽

Better Than

Abstract A simple sweep co-distillation method which uses the Storherr tube was developed for cleanup of 2 g or less of crude crop extracts which contain organophosphate pesticide residues. Five crops (kale, carrots, apples, strawberries, and potatoes) were fortified at levels of 1.0, 0.5, and 0.1 ppm with a mixture containing Trithion, diazinon, malathion, methyl parathion, and parathion. The sweep co-distillation method was compared with the adsorption column method by use of this mixture. The range of average per cent recoveries were 89–101% and 83–96%, respectively. The cleanup required approximately 20 minutes per sample and was as good as, and in many cases better than, adsorption column chromatography. Detection of the organophosphate pesticides was performed by GLC with the thermionic detector.

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Gas Chromatography with Microcoulometric Detection for Pesticide Residue Analysis

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/47.5.845 ◽

1964 ◽

Vol 47 (5) ◽

pp. 845-859

Author(s):

Jerry Burke ◽

Wendell Holswade

Keyword(s):

Detection System ◽

Residue Analysis ◽

Detection Technique ◽

General Level ◽

Chlorinated Pesticides ◽

Efficient Operation ◽

Column Temperature ◽

Relative Retention ◽

Minimum Number ◽

Multiple Detection

Abstract Conditions are given for the most efficient operation of the microcoulometric gas chromatograph as a multiple detection technique for residues of chlorinated pesticides. Conditions are as follows: Column, aluminum, 6’ long by 4.5 mm i.d., packed with 10% DC 200 silicone fluid (12,500 est) on 80/90 mesh Anakrom ABS (conditioned 1—5 days at 250°C), 210°C column temperature, and 120 ml/min. N2 flow. Chromatography of certain pesticides is improved by injection of cleaned up crop extracts. Columns with a minimum number of bends are superior to coiled columns. Chromatography is not improved by using glass columns. Relative retention times and instrument sensitivity are tabulated for 87 chlorinated and 26 thio pesticide chemicals. Theoretical chloride recoveries are given for 14 compounds and sulfur recoveries for 3 compounds. Theoretical recoveries indicate that the MCGC system is linear for a particular pesticide when it is present above some minimum quantity. Sample cleanup is essential for consistently accurate and reproducible results. The general level of "maximum sensitivity" of this multiple detection technique is approximately 0.01 ppm. The specificity of the detection system (for CI-, Br-, I- or sulfur) is the instrument's greatest virtue.

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Improved separation of fetal hemoglobin by mini-column chromatography.

Clinical Chemistry ◽

10.1093/clinchem/33.2.288 ◽

1987 ◽

Vol 33 (2) ◽

pp. 288-289

Author(s):

L G Morin ◽

E G Barton

Keyword(s):

Column Chromatography ◽

Fetal Hemoglobin ◽

Total Hemoglobin ◽

Better Than

Abstract We present chromatographic conditions for separating and measuring fetal hemoglobin on a 5-cm column of Sephadex CM-50. A distinct fetal band is evident, even when present at less than 1% of total hemoglobin. Precision (CV) of better than 5% is achievable.

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Preparative Purification of Epigallocatechin-3-gallate (EGCG) from Tea Polyphenols by Adsorption Column Chromatography

Chromatographia ◽

10.1007/s10337-014-2764-z ◽

2014 ◽

Vol 77 (23-24) ◽

pp. 1643-1652 ◽

Cited By ~ 2

Author(s):

Weitao Wang ◽

Chaoyang Ma ◽

Shangwei Chen ◽

Song Zhu ◽

Zaixiang Lou ◽

...

Keyword(s):

Column Chromatography ◽

Tea Polyphenols ◽

Adsorption Column

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Extraction and Purification of Polyphenolic Compounds Obtained from Hsian-Tsao (Mesona Procumbens Hemsl.)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.1790 ◽

2012 ◽

Vol 550-553 ◽

pp. 1790-1795 ◽

Cited By ~ 1

Author(s):

Zhi Xian Huang ◽

Ting Qiu ◽

Xiao Cui Lin ◽

Yan Xiang Wu

Keyword(s):

Lipid Peroxidation ◽

Column Chromatography ◽

Polyphenolic Compounds ◽

Maximum Amount ◽

Flavonol Glycoside ◽

Acetone Extract ◽

Adsorption Column ◽

Extraction And Purification ◽

Polyphenolic Content ◽

First Time

Extraction and purification of polyphenolic compounds from Hsian-tsao (Mesona procumbens Hemsl.) were investigated. The polyphenolic compounds were extracted by using acetone, ethanol or methanol at three different concentrations. The polyphenolic concentration and the inhibition of lipid peroxidation were determined. The results showed that, among solvents tested, 75% acetone solvent extracted a maximum amount of polyphenolic compounds from Hsian-tsao. The 75% acetone extract was purified further by AB-8 adsorption column chromatography and eight fractions, A~H, were obtained. Among eight fractions, Fraction E had the highest polyphenolic content and inhibition(76%). Moreover, Fraction E was separated into four polyphenolic compounds (1~4) by HPLC and each compound reached a purity of more than 98%. The structure of the compound was identified by LC-MS and NMR, and the compound-4 was determined to be astragalin (a flavonol glycoside) which was obtained from HT for the first time.

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Rapid Florisil Cleanup Method for Analysis of Chlorinated Pesticide Residues

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/62.1.85 ◽

1979 ◽

Vol 62 (1) ◽

pp. 85-88

Author(s):

Robert M Stimac

Keyword(s):

Chromatographic Analysis ◽

Residue Analysis ◽

Pesticide Residue Analysis ◽

Wet Milling ◽

Chlorinated Pesticides ◽

Florisil Column ◽

Cleanup Efficiency ◽

Cleanup Procedure ◽

One Step ◽

Corn Wet Milling

Abstract A modification of the current Florisil chromatographic cleanup procedure for pesticide residue analysis is presented. By prewashing the Florisil column with a specified quantity of ethyl ether, many chlorinated pesticides, including dieldrin and endrin, can be eluted in one step. The demonstrated cleanup efficiency of the proposed method eliminates the need for further cleanup, since the concentrated eluate is suitable for gas chromatographic analysis. Recovery of 13 chlorinated pesticides in typical products of corn wet milling ranged from 85 to 115%.

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Rapid Digestion and Cleanup of Animal Tissues for Pesticide Residue Analysis

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/48.3.666 ◽

1965 ◽

Vol 48 (3) ◽

pp. 666-667 ◽

Cited By ~ 1

Author(s):

Ronald L Stanley ◽

Herbert T LeFavoure

Keyword(s):

Acetic Acid ◽

Pesticide Residue ◽

Cellular Structure ◽

Residue Analysis ◽

Acid Mixture ◽

Pesticide Residue Analysis ◽

Animal Tissues ◽

Chlorinated Pesticides ◽

Chromatographic Procedure ◽

The Common

Abstract A method is presented for the rapid digestion and cleanup of animal tissues for pesticide residue analysis. Animal tissues are digested by a perchloric-acetic acid mixture to destroy the cellular structure and quantitatively liberate the pesticide-containing fat. The fat is extracted in n-hexane and destroyed on a sulfuric acid-Celite column. The common chlorinated pesticides (except aldrin, dieldrin, and endrin) can then be determined by a colorimetric or chromatographic procedure.

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