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Accurate mass analysis of ethanesulfonic acid degradates of acetochlor and alachlor using high-performance liquid chromatography and time-of-flight mass spectrometry

E.M. Thurman·Imma Ferrer·R. Parry
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Abstract

Degradates of acetochlor and alachlor (ethanesulfonic acids, ESAs) were analyzed in both standards and in a groundwater sample using high-performance liquid chromatography–time-of-flight mass spectrometry with electrospray ionization. The negative pseudomolecular ion of the secondary amide of acetochlor ESA and alachlor ESA gave average masses of 256.0750±0.0049 amu and 270.0786±0.0064 amu respectively. Acetochlor and alachlor ESA gave similar masses of 314.1098±0.0061 amu and 314.1153±0.0048 amu; however, they could not be distinguished by accurate mass because they have the same empirical formula. On the other hand, they may be distinguished using positive-ion electrospray because of different fragmentation spectra, which did not occur using negative-ion electrospray.

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E.M. Thurman, Imma Ferrer, R. Parry. 2002. Accurate mass analysis of ethanesulfonic acid degradates of acetochlor and alachlor using high-performance liquid chromatography and time-of-flight mass spectrometry. https://doi.org/10.1016/s0021-9673(01)01470-4

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