Green synthesis of magnetic aromatic polyamide composites via mechanochemical ball milling with a deep eutectic system for the magnetic solid-phase extraction of antibiotics from water

Magnetic aromatic polyamide (MAPA) composites were synthesized using a green mechanochemical ball milling process and used for magnetic solid-phase extraction (MSPE) and detection of trace level fluoroquinolone antibiotics (FQs) from water samples. The formation of MAPAs was facilitated by deep eutectic systems (DESys) created from magnetic beads and organic monomers during ball milling. A comprehensive study was conducted to investigate the kinetics, thermodynamics, and mechanisms of MAPA adsorption of ciprofloxacin hydrochloride (CIP) and ofloxacin (OFL) from water. The maximum adsorption capacities for CIP and OFL were found to be 151.5 mg/g and 164.1 mg/g, respectively. Additionally, the recyclability and selective adsorption capabilities of MAPAs were evaluated. MAPAs were subsequently used for MSPE of CIP and OFL in water samples. Both UV–Vis spectrometry and HPLC methods can be used for analysis, the MSPE-HPLC method showed superior linearity for CIP (0.06–1500 μg/L) and OFL (1–1200 μg/L), with R² values of 0.9995 and 0.9999, and limit of detection (LOD) as low as 0.006 μg/L and 0.02 μg/L, respectively. Both analytical methods are highly effective and practical for use with real water samples. MAPA used for MSPE offer a promising green approach for detecting antibiotic contamination in aquatic ecosystems.