Magnetic solid phase extraction based on Fe3O4@SiO2@CTS nano adsorbent for the sensitive detection of trace polychlorinated biphenyls in environmental water samples.

[Display omitted] • Magnetic nano adsorbent based on Fe 3 O 4 @SiO 2 @CTS was proposed. • MSPE-GC–MS quantification method was successfully applied to the analysis of PCBs in environmental water samples. • Rapid magnetic separation was obtained for multiple PCBs detection. • The magnetic nano adsorbent could be used at least 10 cycles with high stability. In this study, a magnetic composite material was developed by bonding the modified natural polysaccharide chitosan (CTS) with SiO 2 on the surface of magnetic Fe 3 O 4 nanoparticles to detect polychlorinated biphenyls (PCBs). The structural, porosity, and magnetic properties of Fe 3 O 4 @SiO 2 @CTS were characterized by scanning electron microscopy, infrared spectroscopy, X-ray diffraction, nitrogen sorption, and vibrating sample magnetometry. Various experimental parameters affecting the extraction capacity were investigated, including extraction time, desorption time, desorption solvent, solution pH value, and salt ion concentration. Results showed that Fe 3 O 4 @SiO 2 @CTS exhibited excellent selectivity, easy separation by magnet, and reusability (at least 10 cycles). Under optimized experimental condition, this magnetic solid phase extraction material was applied to detect three PCBs with low limits of detection of 0.02–0.15 μg·L−1. The linear correlation coefficient was higher than 0.998, while the recoveries ranged between 90.34% and 106.99% with the relative standard deviation less than 11.31%. The practical application of Fe 3 O 4 @SiO 2 @CTS was verified through quantitative analysis of PCB residues in environmental water, supporting its promising role in simple, convenient, and low-cost detection of PCBs in real environmental samples. [ABSTRACT FROM AUTHOR]