Selahle Shirley K, Waleng Ngwako J, Mpupa Anele, Nomngongo Philiswa N
Department of Chemical Sciences, University of Johannesburg, Doornfontein Campus, Doornfontein, South Africa.
Department of Science and Innovation/National Research Foundation South African Research Chairs Initiative Chair: Nanotechnology for Water, University of Johannesburg, Doornfontein, South Africa.
Front Chem. 2020 Sep 16;8:555847. doi: 10.3389/fchem.2020.555847. eCollection 2020.
In this study, a magnetic porphyrin-based porous organic polymer (MP-POP) nanocomposite was successfully synthesized according previous studies and applied as an adsorbent for simultaneous extraction and preconcentration of four neonicotinoid insecticides from surface river water. The MP-POP was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS), N-adsorption/desorption analysis, Fourier Transform infrared spectroscopy (FTIR). The neonicotinoid insecticides were quantified using high performance chromatography coupled with diode array detector (HPLC-DAD). The MP-POP shown to have a high surface area, highly porous structure and strong affinity toward the investigated analytes. The adsorption capacities were 99.0, 85.5, 90.0, and 79.4 mg g for acetamiprid, clothiandin, thiacloprid and imidacloprid, respectively. The influential parameters affecting the magmatic μ-solid phase extraction (M-μ-SPE) procedure were investigated using fractional factorial design and surface response methodology (RSM). Under optimum conditions, the method exhibited relatively low limit of detection in the range of 1.3-3.2 ng L, limit of quantification in the range of 4.3-11 ng L and wide linearity (up to 600 μg L). The intraday and interday precision, expressed as the relative standard deviation (RSD) were <5%. The percentage recoveries for the four target analytes ranged from 91 to 99.3% for the spiked river water samples. The method was applied for determination of neonicotinoids in river water samples and concentrations ranged from 0 to 190 ng L.
在本研究中,根据先前的研究成功合成了一种基于磁性卟啉的多孔有机聚合物(MP-POP)纳米复合材料,并将其用作吸附剂,用于同时从地表河水中萃取和预富集四种新烟碱类杀虫剂。使用X射线衍射(XRD)、透射电子显微镜(TEM)、扫描电子显微镜/能量色散X射线光谱(SEM/EDS)、N吸附/脱附分析、傅里叶变换红外光谱(FTIR)对MP-POP进行了表征。使用高效液相色谱结合二极管阵列检测器(HPLC-DAD)对新烟碱类杀虫剂进行定量。结果表明,MP-POP具有高比表面积、高度多孔的结构以及对所研究分析物的强亲和力。对啶虫脒、噻虫胺、噻虫啉和吡虫啉的吸附容量分别为99.0、85.5、90.0和79.4 mg/g。使用分数因子设计和表面响应方法(RSM)研究了影响岩浆微固相萃取(M-μ-SPE)过程的影响参数。在最佳条件下,该方法的检测限相对较低,在1.3 - 3.2 ng/L范围内,定量限在4.3 - 11 ng/L范围内,线性范围宽(高达600 μg/L)。以相对标准偏差(RSD)表示的日内和日间精密度<5%。加标河水样品中四种目标分析物的回收率在91%至99.3%之间。该方法用于测定河水样品中的新烟碱类物质,浓度范围为0至190 ng/L。