Determination of Acephate in Vegetables by Magnetic Molecularly Imprinted Polymer Isolation Coupled with High-Performance Liquid Chromatography

Abstract

Magnetic molecularly imprinted polymers based on carbon nanotubes were prepared and characterized by infrared spectrometry, transmission electron microscopy, and vibrating sample magnetometry and were employed for the isolation of acephate from cabbage, spinach, lettuce, leeks, and celery. Kinetic and recognition studies were carried out in order to investigate the adsorption properties of the polymers. During the application process, the acephate extracted from vegetables was purified with the magnetic molecularly imprinted polymers and determined by high performance liquid chromatography with an ultraviolet detector. The recoveries of acephate at three fortified concentrations (0.015, 0.15, and 1.5 mg kg−1) were between 89.2% and 93.4%. The limits of detection and quantification of acephate were 0.0025 and 0.0077 mg kg−1, respectively. The linear dynamic range was from 0.01 to 5 mg kg−1. The relative standard deviations of intra- and inter-day precision were 1.1% to 5.9% and 2.7% to 6.4%, respectively. The developed method was demonstrated to be rapid and selective for the extraction and determination of acephate in vegetables.