Farajzadeh Mir Ali, Mohammad Mehri Sina, Afshar Mogaddam Mohammad Reza
Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran; Engineering Faculty, Near East University, 99138 Nicosia, North Cyprus, Mersin 10, Turkey.
Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
J Chromatogr A. 2025 Jan 25;1741:465608. doi: 10.1016/j.chroma.2024.465608. Epub 2024 Dec 18.
This paper introduces an innovative technique for extracting pesticides from herbal infusions using a core-shell magnetic adsorbent (i.e., Cu-BTC@FeO) where achieving a notable enrichment factor for the target pesticides by coupling with a dispersive liquid-liquid microextraction method. To validate the successful synthesis of the adsorbent, a range of analytical techniques were utilized including vibrating sample magnetometer, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray, and Brunauer-Emmett-Teller analyses. A vortex agitation and an external magnetic field were used during the extraction process to aid the analytes' desorption and adsorbent separation, respectively. Also, a mixture of iso-propanol and deionized water was used to desorb the analytes from the adsorbent surface. The resulting supernatant containing the desorbed pesticides was mixed with 1,2-dibromoethane as the extraction solvent and then injected into an aqueous medium. After centrifugation, 1 μL of the sedimented phase was introduced into the gas chromatograph system equipped with a flame ionization detector. The reliability of the proposed methodology was confirmed by obtaining low relative standard deviations (1.0-8.5 %), acceptable extraction recoveries (39-93 %), substantial enrichment factors (195-475), calibration curve linearity (r=0.993-0.998), and significantly low limits of quantification (0.34-3.0 μg L) and detection (1.1-9.9 μg L). Absence of matrix effects with relative recovery values of 80-120 % for real samples, minimal use of the adsorbent and extraction solvent, a reduction in extraction time due to the elimination of two centrifugation steps (facilitated by an external magnetic field), and the use of environmentally friendly solvents collectively highlight the advantages and significant values of this approach.
本文介绍了一种使用核壳磁性吸附剂（即Cu-BTC@FeO）从草药浸液中提取农药的创新技术，该技术通过与分散液液微萃取方法相结合，实现了目标农药显著的富集因子。为验证吸附剂的成功合成，使用了一系列分析技术，包括振动样品磁强计、扫描电子显微镜、透射电子显微镜、傅里叶变换红外光谱、X射线衍射、能量色散X射线和布鲁诺尔-埃米特-泰勒分析。在萃取过程中，分别使用涡旋搅拌和外部磁场来辅助分析物的解吸和吸附剂分离。此外，使用异丙醇和去离子水的混合物从吸附剂表面解吸分析物。将含有解吸农药的上清液与作为萃取溶剂的1,2-二溴乙烷混合，然后注入水介质中。离心后，将1μL沉淀相引入配备火焰离子化检测器的气相色谱系统。所提出方法的可靠性通过获得低相对标准偏差（1.0-8.5%）、可接受的萃取回收率（39-93%）、显著的富集因子（195-475）、校准曲线线性（r=0.993-0.998）以及极低的定量限（0.34-3.0μg/L）和检测限（1.1-9.9μg/L）得到证实。实际样品的相对回收率值为80-120%，不存在基质效应，吸附剂和萃取溶剂使用量极少，由于消除了两个离心步骤（借助外部磁场）而缩短了萃取时间，以及使用环境友好型溶剂，这些共同突出了该方法的优点和重要价值。
