Elfiky Mona, Abdo Moa'mena, Darwesh Mona, Salahuddin Nehal
Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt.
Basic Sciences Department, the Higher Institute of Engineering, Kafr El-Sheikh, Egypt.
Mikrochim Acta. 2024 Dec 24;192(1):30. doi: 10.1007/s00604-024-06765-8.
The detection of 4-chloro-2-methylphenoxyacetic acid (CMPA) herbicide is crucial due to the potential health risks linked to exposure through drinking water, air, and food, which may adversely affect liver and kidney functions. To address this environmental concern and promote sustainable agriculture, a sensitive carbon paste sensor incorporating a composite material was developed. The composite sensor is based on porous cobalt-1,4-benzenedicarboxylate metal-organic framework and exfoliated montmorillonite nanolayers (Co-OF/MMt). This sensor enables the voltammetric detection of CMPA in real soil samples using linear sweep adsorptive anodic stripping voltammetry (LS-AdASV), facilitating early and accurate monitoring of herbicide levels. The Co-OF/MMt nanocomposite was synthesized via a hydrothermal method involving the precipitation of Co-OF in the presence of MMt. Comprehensive characterization of the synthesized materials was carried out using Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), SEM-Energy dispersive X-ray spectroscopy (SEM-EDX) and surface area analysis (BET). The resulting modified carbon paste sensor, utilizing 1.0% Co-OF/MMt nanocomposite, exhibited superior electrochemical properties compared with the bare carbon paste sensor, possessing an electroactive surface area of 1004.1 m/g with a minimal resistivity (R) of 330 Ω. Under standard operating conditions, the developed sensor demonstrated detection limits of 0.03 nM and 0.1 nM across two broad linear ranges (0.03 to 0.10 nM - 0.10 to 1.0 nM) and (0.1 to 1.0 nM - 1.0 to 7.0 nM), respectively, for CMPA determination in both bulk and soil samples. These results pointed out the promising electrochemical modified sensor for the direct and simple detection of certain herbicides in environmental matrices, without the need for sample pretreatment steps. This capability supports sustainable development goals by enhancing effective environmental monitoring.
检测4-氯-2-甲基苯氧基乙酸（CMPA）除草剂至关重要，因为通过饮用水、空气和食物接触该除草剂存在潜在健康风险，可能会对肝脏和肾脏功能产生不利影响。为了解决这一环境问题并促进可持续农业发展，研发了一种包含复合材料的灵敏碳糊传感器。该复合传感器基于多孔钴-1,4-苯二甲酸金属有机框架和剥离的蒙脱石纳米层（Co-OF/MMt）。此传感器能够使用线性扫描吸附阳极溶出伏安法（LS-AdASV）对实际土壤样品中的CMPA进行伏安检测，便于早期准确监测除草剂水平。Co-OF/MMt纳米复合材料通过水热法合成，即在MMt存在的情况下使Co-OF沉淀。使用傅里叶变换红外光谱（FT-IR）、X射线粉末衍射（XRD）、扫描电子显微镜（SEM）、SEM-能量色散X射线光谱（SEM-EDX）和表面积分析（BET）对合成材料进行了全面表征。所得的修饰碳糊传感器使用1.0%的Co-OF/MMt纳米复合材料，与裸碳糊传感器相比表现出优异的电化学性能，其电活性表面积为1004.1 m/g，最小电阻率（R）为330 Ω。在标准操作条件下，对于批量和土壤样品中的CMPA测定，所开发的传感器在两个宽线性范围内（0.03至0.10 nM - 0.10至1.0 nM）和（0.1至1.0 nM - 1.0至7.0 nM）的检测限分别为0.03 nM和0.1 nM。这些结果表明，该电化学修饰传感器有望直接、简单地检测环境基质中的某些除草剂，无需样品预处理步骤。这种能力通过加强有效的环境监测来支持可持续发展目标。
