Alam Samsul, Srivastava Neha, Iqbal Nusrat, Saini Mahesh Kumar, Kumar Jitendra
Analytical Division, Institute of Pesticide Formulation Technology (IPFT), Sector-20, Udyog Vihar, Gurgaon, Haryana, India.
J AOAC Int. 2021 Jun 12;104(3):633-644. doi: 10.1093/jaoacint/qsaa156.
For the analysis of pesticide residues in water samples, various extraction techniques are available. However, liquid-liquid extraction (LLE) and solid-phase extraction (SPE) are most commonly used. LLE and SPE extraction techniques each have their own disadvantages.
The aim of the study was to develop an environment-friendly multi-residue method for determination of multiclass pesticides in environmental water samples (ground water, agricultural field/irrigation run-off water, etc.).
The magnetic solid-phase extraction (MSPE) technique using surface-fabricated magnetic nano-particles was used for extraction of water samples, followed by quantification by gas chromatography tandem mass spectrometry. The developed multi-residue method was validated in terms of linearity, LOD, LOQ, recovery, and repeatability.
Recovery data were obtained at the spiking concentration level of 1, 5, and 10 µg/L, yielding recoveries in the range of 70-120%. Overall, non-polar pesticides from all the groups, i.e., synthetic pyrethroid, organophosphorus, organochlorine, herbicides, and fungicides, show acceptable recovery percentages. Good linearity (r2 value ≥ 0.99) was observed at the concentration range of 0.5-100 µg/L. RSD values were found ≤ 18.8.
The study shows that the method is specific, rapid, and low cost, as well as having a good linearity and recovery; thus, this method is applied in routine purposes for the analysis of pesticide residue in real water samples.
Due to better adsorption ability, permeability, and magnetic separability, the functionalized nano-particles were found effective in the enrichment of 22 multiclass pesticides including organo-phosphorus, organo-chlorine, synthetic pyrethroid, herbicides, and fungicides.
对于水样中农药残留的分析，有多种提取技术可供选择。然而，液液萃取（LLE）和固相萃取（SPE）是最常用的。LLE和SPE提取技术都有各自的缺点。
本研究的目的是开发一种环境友好的多残留方法，用于测定环境水样（地下水、农田/灌溉径流等）中的多类农药。
使用表面制备的磁性纳米颗粒的磁性固相萃取（MSPE）技术对水样进行萃取，然后通过气相色谱串联质谱进行定量。所开发的多残留方法在线性、检测限、定量限、回收率和重复性方面进行了验证。
在加标浓度为1、5和10μg/L时获得回收率数据，回收率范围为70-120%。总体而言，所有组中的非极性农药，即拟除虫菊酯、有机磷、有机氯、除草剂和杀菌剂，显示出可接受的回收率百分比。在0.5-100μg/L的浓度范围内观察到良好的线性（r2值≥0.99）。相对标准偏差值≤18.8。
该研究表明该方法具有特异性、快速、低成本，以及良好的线性和回收率；因此，该方法可用于实际水样中农药残留分析的常规目的。
由于具有更好的吸附能力、渗透性和磁分离性，功能化纳米颗粒被发现可有效富集包括有机磷、有机氯、拟除虫菊酯、除草剂和杀菌剂在内的22种多类农药。
