Determination of Atrazine in Vegetables with Extraction by a Magnetite–Chitosan Molecularly Imprinted Polymer and Gas Chromatography

ABSTRACT

Core–shell magnetic molecularly imprinted polymers were prepared using ferroferric oxide modified with chitosan as the carrier, atrazine as the template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The structure of the magnetic polymers were characterized by infrared spectroscopy, vibrating sample magnetometer spectroscopy, X-ray diffraction, and thermogravimetric analysis. The attraction of the imprinted polymers for atrazine was studied through static equilibrium binding. The maximum adsorption capacity was 12.5 mg g⁻¹. The adsorption mechanism was shown to fit the Langmuir model through monolayer adsorption. The magnetic polymers were used for solid-phase extraction and gas chromatography for the determination of atrazine in vegetables. The recoveries were between 80.4 and 91.6% with relative standard deviations lower than 4.9%.

KEYWORDS:

• Atrazine
• chitosan
• gas chromatography
• magnetic molecularly imprinted polymers
• solid-phase extraction