Electron capture gas-liquid chromatographic method for the simultaneous analysis of 2,4-D, dicamba, and mecoprop residues in soil, wheat, and barley
Khan, S.U.
Journal - Association of Official Analytical Chemists 58(5): 1027-1031
1975
ISSN/ISBN: 0004-5756 PMID: 1158822 Document Number: 91152
A method has been developed for the simultaneous analysis of 2,4-D, dicamba, and mecoprop residues in soil, wheat, and barley. Soil and crop samples are extracted with acidic acetone and methanol, respectively. The extracts in diethyl ether are esterified with diazomethane and cleaned up by passing through a Florisil column. Extracts are analyzed by g.l.c., using an electron capture detector to determine 2,4-D and dicamba residues. Mecoprop in the extract is not detected at low levels of concn. However, bromination of the extract increases the response of the electron capture detector to mecoprop. The method is sensitive to about 0.15 ppm. of 2,4-D and dicamba and 0.5 ppm. mecoprop. Recoveries of these 3 herbicides added to soil, wheat and barley samples at 0.05-, 0.1-, 0.5-, and 1-ppm. levels were between 65 and 93%. The method was used for the simultaneous analysis of 2,4-D, dicamba and mecoprop residues in wheat, barley and soil samples obtained from fields sprayed with a mixture of these herbicides. From summary.