Efficient solid phase extraction and HPLC analysis of drug residues in Animal-Derived food products using Polyoxometalate-based ionic liquid composite

In this study, composite as Fe₃O₄@SiO₂ coated with a polyoxometalate based ionic liquid was synthesized and applied as an adsorbent for magnetic solid phase solid-phase extraction (MSPE) of drug residues. The prepared composite was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The proposed method was used to extract and analyze drug residues (amoxicillin, paracetamol, levofloxacin, and cefixime) food samples such as milk, meat and water samples by HPLC. The resultant adsorbent exhibited superb magnetic properties, high surface area, and strong interactions, enabling effective extraction of drug residues. Critical parameters affecting MSPE performance, such as adsorbent amount, extraction time, concentration of drugs, pH, and reusability were systematically optimized. The HPLC method demonstrated excellent linearity ranges of (0.05–100 µg/mL, R² ≥ 0.994) and low limits of detection (0.05 to 0.09 µg/mL) for drug residues. The recovery of drug residues from meat, milk, and water samples ranges from 90.62–96.92 %. The prepared nanocomposite exhibited good reusability after eight successive recycles. Overall, this study presents a powerful analytical strategy that integrates magnetic separation, ionic liquid-based extraction, and HPLC analysis for rapid, sensitive, and simultaneous quantification of drug residues in food, addressing the growing concerns over food safety and environmental pollution.