Magnetic Solid Phase Extraction Based on Nanostructured Magnetic Porous Porphyrin Organic Polymer for Simultaneous Extraction and Preconcentration of Neonicotinoid Insecticides From Surface Water.

Shirley K Selahle,Philiswa N Nomngongo,Ngwako J Waleng,Anele Mpupa

doi:10.3389/fchem.2020.555847

Abstract

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), N2-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−1 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−1, limit of quantification in the range of 4.3–11 ng L−1 and wide linearity (up to 600 μg L−1). 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−1.

Highlights

Neonicotinoid insecticides are applied worldwide to combat unwanted insects from attacking crops which led to their entry into the environment (Goulson, 2013; Klarich et al, 2017; Hladik et al, 2018)
Indicates the N-H peak, and followed by a smaller and sharp peak at around 2,986 cm−1 which is for phenyl (Wang et al, 2017, 2018a,b)A peak for alkene carbons (C=C) in the pyrrole ring was observed at 1,604 cm−1 and Fe-N peak at 1,047 cm−. 1 The Fe-N peak shows that the magnetic iron was successfully incorporated on the porous organic polymers (POPs) without any alterations (Wang et al, 2017, 2018a,b)
A rapid, simple, reliable and efficient UA-DMSPE/HPL-DAD method was developed for the simultaneous extraction, preconcentration determination of acetamiprid, clothiandin, thiacloprid, and imidacloprid in river water samples

Summary

Introduction

Neonicotinoid insecticides are applied worldwide to combat unwanted insects from attacking crops which led to their entry into the environment (Goulson, 2013; Klarich et al, 2017; Hladik et al, 2018). Over- application of neonicotinoid insecticides in the environment can cause negative effects on human health and living organisms (Klarich et al, 2017; Struger et al, 2017). The permissible maximum residue limits for neonicotinoid insecticides have been controlled by the Codex Alimentarius Commision and European Union and World Health Organization to protect human health (Vichapong et al, 2016). These regulated limits are only applicable to crops and soil, not to portable water, river water, water reservoirs and surface or ground water (Vichapong et al, 2015, 2016). To ensure safe water to humans and living organisms, an effective technique for the detection of the neonicotinoid insecticides in surface water, portable water, river water and water reservoirs is of remarkable significance

Objectives

Results

Conclusion