title: Detection of three herbicide, and one metabolite, residues in brown rice and rice straw using various versions of the QuEChERS method and liquid chromatography-tandem mass spectrometry.
abstract: A single-run analytical method was developed to analyze the three herbicides azimsulfuron, bensulfuron-methyl, and mesotrione and its metabolite (4-methylsulfonyl-2-nitrobenzoic acid (MNBA)) in brown rice and rice straw using liquid chromatography-tandem mass spectrometry (LC/MS/MS). Samples extracted using various versions of Quick, Easy, Cheap, Effective, Rugged, and Safe "QuEChERS" (original unbuffered, acetate (AOAC), and citrate (EN) buffered) methods gave poor recoveries of all the tested analytes in both matrices. The extraction efficiency was improved when primary-secondary amine (PSA) sorbent was removed from the purification step, with the best recovery being achieved for EN-QuEChERS, which was subsequently used throughout the study. Overall, a determination coefficients (R(2))⩾0.995 was achieved at matrix-matched calibration curves at various concentration ranges. The recovery rates at three fortification levels (limit of quantification (LOQ), 1/2 maximum residue limit (1/2MRL), and MRL) ranged from 78 to 114.5, with relative standard deviations (RSDs)<18% for all the tested analytes in both matrices. The LOQs for all herbicides were lower than the MRL set by the Ministry of Food and Drug Safety (MFDS), Republic of Korea. Field trials with the recommended, or double the recommended dose, revealed that the herbicides can safely be applied to rice, as no residues were detected in the harvested samples at 110days.
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Young-Jun
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Md Musfiqur
authors.initials: MM
authors.lastname: Rahman
authors.affiliation: Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul, Repulic of Korea; Department of Pharmacology, Faculty of Veterinary Medicine, Cairo University, 12211 Giza, Egypt. Electronic address: abdelaty44@hotmail.com.
authors.forename: A M
authors.initials: AM
authors.lastname: Abd El-Aty
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Jeong-Heui
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Hyung Suk
authors.initials: HS
authors.lastname: Chung
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Sung-Woo
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Water Pollution Research Department, National Research Centre, 33 El Bohouth St., Dokki, 12622 Giza, Egypt.
authors.forename: Azza M
authors.initials: AM
authors.lastname: Abdel-Aty
authors.affiliation: Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul, Repulic of Korea.
authors.forename: Ho-Chul
authors.initials: HC
authors.lastname: Shin
authors.affiliation: Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea. Electronic address: jhshim@chonnam.ac.kr.
authors.forename: Jae-Han
authors.initials: JH
authors.lastname: Shim
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D006540:Herbicides / Q000032:analysis; D012275:Oryza / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D006540:Herbicides; D010573:Pesticide Residues
keywords: Herbicides; LC/MS/MS; QuEChERS; Residues; Rice; Rice straw