Facile fabrication of a novel SPME fiber based on silicone sealant/hollow ZnO@CeO2 composite with super-hydrophobicity for the enhanced capture of pesticides from water

Abstract

Herein, a novel solid phase microextraction (SPME) fiber coating based on silicone sealant/hollow ZnO@CeO2 composite with super-hydrophobicity was designed, which could capture rapidly and determine efficiently-six pesticides combined with high-performance liquid chromatography (HPLC). The synthesis mechanism of ZnO@CeO2 with core–shell structure was discussed. Under the optimized conditions, the developed method showed a wide linear range (0.026–200 µg/L) with good linearity (R2 greater than 0.9988), low detection limits (0.008–0.353 µg/L, S/N = 3), and quantification limits (0.026–1.175 µg/L, S/N = 10) for six pesticides. The relative standard deviations (RSD) of single fiber and different batches of fibers were 0.4–4.8 % and 0.6–5.3 %, respectively. In addition, compared with the commercial SPME fiber, the fiber showed better enrichment ability and extraction efficiency for pesticides, which might be due to the solid π-π accumulation, hydrophobic interaction, abundant adsorption sites, and hydrogen bonding between the coating and the target analyte. Besides, the hollow structure of the composite material, the rare earth metal oxide CeO2 on the surface of the coating, and the silicone sealant all played a crucial role in the extraction process. Finally, the method had been successfully applied to determine the pesticides in real water samples, with the recovery rate ranging from 80.1 % to 108.2 % and RSD < 5.67 %. The experimental results showed that the Ss/ZnO@CeO2 with a hollow core–shell structure had great application potential as a composite coating for solid-phase microextraction.