Nanoporous carbon derived ZIF-67@MWCNTs-Fe3O4 reinforced hollow fiber to performe hollow fiber solid-phase micro extraction (HF-SPME) coupled with high-performance liquid chromatography to determine deltamethrin and cypermethrin

This study presents a novel micro extraction approach by developing a highly porous and stable Co@N-C/MWCNTs sorbent capable to addresses limitations of traditional sorbents. Zeolitic Imidazolate Framework-67 (ZIF-67) interconnected with magnetic Multi-walled Carbon Nanotubes (MWCNTs) selected as the template for the synthesis of sorbent possess distinctive N-doped and metal (Co) active sites coupled with carbon-rich nanotubes, resulting in a sorbent with a strong affinity to target analytes and excellent chemical stability. For the first time, this material integrated into the pores of a hollow fiber (HF) for a simplified and efficient Hollow Fiber Solid Phase Micro extraction (HF-SPME) method. This innovative integration increases the extraction surface area and minimize matrix interference. Under optimal conditions, the method achieved a wide linear range (0.1–200 μg L⁻¹) for the target analytes, deltamethrin (DLT) and cypermethrin (CPM), the coefficient of determination of 0.9945 for DLT and 0.9982 for CPM. Additionally, it demonstrated excellent analytical performance with: Low limits of detection (LODs): 0.03 µg L⁻¹ for DLT and 0.04 µg L⁻¹ for CPM. Good precision: Inter and intra-day relative standard deviations (RSD) within 2.5–3.4 %. High enrichment factors (EFs): 68–58. The novel Co@N-C/MWCNTs coating, integrated with a hollow fiber, offers a promising advancement for HF-SPME due to its unique properties.