Optimization of a modified QuEChERS method by an n-octadecylamine-functionalized magnetic carbon nanotube porous nanocomposite for the quantification of pesticides

Abstract In this work, the adoption of n-octadecylamine (ODA) functionalized magnetic carbon nanotube porous nanocomposite (M-CNTs/ODA) as cleanup agents for a modified QuEChERS method to detect pesticide residues was investigated for the first time. The properties and morphology of the M-CNTs/ODA were characterized by transmission electron microscopy, vibrating sample magnetometer and X-ray diffraction. The results confirmed that M-CNTs/ODA had an excellent ability to remove matrix interferences and reduce matrix effects compared with traditional cleanup agents. The recoveries ranged from 81.3%-96.1%, the relative standard deviations (RSDs) varied from 1.98% to 6.89% (n = 3), the limits of detection (S/N = 3) of the method for the compounds were between 0.009-0.050 mg/L in real samples. Satisfactory results were also obtained for the detection of 16 pesticides in vegetables and fruits. As a promising cleanup material, the porous M-CNTs/ODA has future application potential in detecting other organic pollutants in different samples.