Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100193, China.
Chemosphere. 2014 Jan;95:33-40. doi: 10.1016/j.chemosphere.2013.07.085. Epub 2013 Sep 2.
In this study, a simple and rapid multi-pesticide residues analytical method has been developed and evaluated for simultaneous identification and quantification of 30 organophosphorus pesticides (OPPs) present at trace levels in perennial Morinda roots. Samples were firstly extracted and cleaned up with a streamlined method (modified QuEChERS), and then detected by gas chromatography with flame photometric detector (GC-FPD). For accurate quantification, representative matrix-matched calibration curves were applied to compensate matrix effects. Reasonable linearity was found in the concentration ranges of 0.04 and 1.28 μg mL(-1), with correlation coefficients r better than 0.9921 (0.9921-0.9998). The limits of detection (LODs) were between 0.005 and 0.02 μg mL(-1) for all investigated pesticides, while the limits of quantification (LOQs) were in the range of 0.01-0.04 μg mL(-1), below the regulatory maximum residue limits (MRL) suggested. Acceptable quantitative recoveries of 75.01-118.89% (96.0% on average) were achieved with relative standard deviations (RSD) varying from 0.89% to 9.80% (5.39% on average) at three different concentration levels of 0.05, 0.1 and 1.0 mg kg(-1). Out of all 40 batches of real samples, only fenitrothion was found in two samples, which was successfully confirmed by GC-MS. Based on these results, this analytical method has been proven to be fast, robust, accurate, selective, sensitive and easy to operate in the analysis of multiple pesticide residues in Morinda roots. Meanwhile, it also draws attention to the need of pesticide monitoring programs in local soils.
本研究建立并评价了一种简单、快速的多农药残留分析方法，用于同时鉴定和定量测定痕量存在于多年生菝葜根中的 30 种有机磷农药（OPPs）。样品首先采用简化方法（改良的 QuEChERS）提取和净化，然后用气相色谱-火焰光度检测器（GC-FPD）检测。为了准确定量，采用代表性基质匹配校准曲线来补偿基质效应。在 0.04 和 1.28μg/mL 的浓度范围内，得到了合理的线性关系，相关系数 r 均大于 0.9921（0.9921-0.9998）。所有研究农药的检出限（LODs）均在 0.005-0.02μg/mL 之间，定量限（LOQs）在 0.01-0.04μg/mL 之间，均低于建议的监管最大残留限量（MRL）。在 0.05、0.1 和 1.0mg/kg 三个不同浓度水平下，可获得 75.01-118.89%（平均 96.0%）的可接受定量回收率，相对标准偏差（RSD）在 0.89%-9.80%之间（平均 5.39%）。在 40 批实际样品中，仅在 2 批样品中发现了三唑磷，并用 GC-MS 成功确认。基于这些结果，该分析方法已被证明在分析菝葜根中的多种农药残留时快速、稳健、准确、选择性好、灵敏度高且易于操作。同时，它还提醒人们需要对当地土壤中的农药监测计划进行关注。
