Biotechnology Research Institute, College of Agriculture and Life Sciences, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
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.
Food Chem. 2016 Nov 1;210:442-50. doi: 10.1016/j.foodchem.2016.05.005. Epub 2016 May 2.
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.
建立了一种单步分析方法，采用液相色谱-串联质谱（LC/MS/MS）分析糙米和稻草中的三种除草剂莠去津、苄嘧磺隆和麦草畏及其代谢物（4-甲基磺酰基-2-硝基苯甲酸（MNBA））。使用各种版本的快速、简便、廉价、有效、坚固和安全（QuEChERS）（原始非缓冲、乙酸盐（AOAC）和柠檬酸盐（EN）缓冲）方法提取的样品在两种基质中对所有测试分析物的回收率都很差。当净化步骤中去除初级-次级胺（PSA）吸附剂时，提取效率得到提高，EN-QuEChERS 的回收率最高，随后在整个研究中均使用该方法。总体而言，在基质匹配校准曲线上在各种浓度范围内均实现了测定系数（R(2)）≥0.995。在三个添加水平（定量限（LOQ）、1/2 最大残留限量（1/2MRL）和 MRL）下的回收率范围为 78-114.5%，两种基质中所有测试分析物的相对标准偏差（RSD）均<18%。所有除草剂的 LOQ 均低于韩国食品药品安全部（MFDS）设定的 MRL。推荐剂量或推荐剂量的两倍的田间试验表明，这些除草剂可以安全地用于水稻，因为在 110 天时收获的样品中未检测到残留。
