title: Simultaneous analysis of herbicides pendimethalin, oxyfluorfen, imazethapyr and quizalofop-p-ethyl by LC-MS/MS and safety evaluation of their harvest time residues in peanut (Arachis hypogaea L.).
abstract: This paper reports a simple and rapid method for simultaneous determination of the residues of selected herbicides viz. pendimethalin, oxyfluorfen, imazethapyr and quizalofop-p-ethyl in peanut by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A modified approach of the QuEChERS methodology was used to extract the herbicides from the peanut kernel without any clean-up. The method showed excellent linearity (r(2) > 0.99) with no significant matrix effect. Accuracy of the method in terms of average recoveries of all the four herbicides ranged between 69.4 -94.4 % at spiking levels of 0.05, 0.10 and 0.25 mg kg(-1) with intra-day and inter-day precision RSD (%) between 2.6-16.6 and 8.0-11.3, respectively. Limit of quantification (LOQs) was 5.0 μg kg(-1) for pendimethalin, imazethapyr and quizalofop-p-ethyl and 10.0 μg kg(-1) for oxyfluorfen. The expanded uncertainties were <11 % for determination of these herbicides in peanut. The proposed method was successfully applied for analysis of these herbicide residues in peanut samples harvested from the experimental field and the residues were below the detection level.
authors.affiliation: Directorate of Groundnut Research, Junagadh, 362001 Gujarat India.
authors.forename: Ajoy
authors.initials: A
authors.lastname: Saha
authors.affiliation: National Referral Laboratory, National Research Centre for Grapes Pune, 412307 Maharashtra, India.
authors.forename: Ahammed
authors.initials: A
authors.lastname: Shabeer T P
authors.affiliation: National Referral Laboratory, National Research Centre for Grapes Pune, 412307 Maharashtra, India.
authors.forename: Kaushik
authors.initials: K
authors.lastname: Banerjee
authors.affiliation: National Referral Laboratory, National Research Centre for Grapes Pune, 412307 Maharashtra, India.
authors.forename: Sandip
authors.initials: S
authors.lastname: Hingmire
authors.affiliation: Directorate of Groundnut Research, Junagadh, 362001 Gujarat India.
authors.forename: Debarati
authors.initials: D
authors.lastname: Bhaduri
authors.affiliation: Directorate of Groundnut Research, Junagadh, 362001 Gujarat India.
authors.forename: N K
authors.initials: NK
authors.lastname: Jain
authors.affiliation: National Referral Laboratory, National Research Centre for Grapes Pune, 412307 Maharashtra, India.
authors.forename: Sagar
authors.initials: S
authors.lastname: Utture
keywords: Herbicides; LC-MS/MS; Modified QuEChERS; Peanut; Safety evaluation