LAUSR

A new type of magnetic material based on silica-coated mixed iron hydroxides functionalized with deep eutectic solvent was utilized for the magnetic solid-phase extraction of organochlorine pesticides prior to gas chromatography-mass spectrometry analysis. Choline chloride and phenol were selected as the hydrogen bond acceptor and donor, respectively, for preparing the deep eutectic solvent-modified magnetic surface. The modified surface possessed superior enrichment capability for organochlorine pesticides. Under optimal extraction conditions, viz., 10 mg sorbent, 5 mL sample solution, and 200 μL acetone (desorption solvent), linearity was obtained in the range 0.005-200 μg L-1 , with coefficients of determination greater than 0.997. The limits of detection and quantification were as low as 0.6-10 ng L-1 and 5-60 ng L-1 , respectively, whereas the enrichment factors were in the range 31-100. The precisions evaluated in terms of the relative standard deviations of the intra- and inter-day experiments were below 4.9% and 7.6%, respectively. The developed method was successfully applied for determining the organochlorine residues in agricultural products. Satisfactory recoveries in the range of 71.2-110.3% were obtained, with a relative standard deviation of less than 8.0%. The proposed material is a promising sorbent for the preconcentration of organochlorine residues. This article is protected by copyright. All rights reserved.