Application of Fe3O4@CNFs combined with deep eutectic solvent-based dual microextraction: a novel and green strategy for rapid determination of pesticides in edible oil samples.

A novel, green, and effective strategy employing Fe3O4-modified carbon nanofibers (CNFs) combined with deep eutectic solvent (DES) is proposed as an extraction agent to extract five pesticides in edible oil samples via dual microextraction modes, followed by high-performance liquid chromatography for determination. The Fe3O4@CNFs nanomaterial and a sequence of hydrophilic DES were prepared at first and then characterized by multiple techniques. Subsequently, the extraction performance of DES and Fe3O4@CNFs-DES was compared and Fe3O4@CNFs-DES exhibited better extraction ability. After that, several influencing parameters such as the composition of DES, the amount of Fe3O4@CNFs-DES, the dispersion methods, and the extraction time were investigated and optimized. Eventually, Fe3O4@CNFs as the solid adsorbent combined with tetrabutylammonium chloride-lactic acid-based DES as the extraction solvent were selected to extract target pesticides from oil samples. The established method received good linearity in the range 25-1000 ng·g-1. The limits of detection for all analytes were in the range 2.25-7.50 ng·mL-1. Satisfactory recoveries of target pesticides were obtained (ranging from 82 to 117%) with a relative standard deviation of 0.26-9.46%. The proposed method has been successfully applied to the rapid detection of target pesticides in oil samples, demonstrating its great potential for quick screening and analysis.