Magnetic Solid-Phase Extraction with Dispersion of Magnetic Hypercrosslinked Polystyrene by Carbon Dioxide for the Extraction of Amphenicols from Honey and Milk in Their Determination by HPLC–MS/MS

A magnetic solid-phase extraction method with the dispersion of magnetic hypercrosslinked polystyrene (MHCPS) by carbon dioxide is proposed for the extraction and preconcentration of amphenicols (chloramphenicol, florfenicol, and thiamphenicol) from honey and milk before their determination by HPLC–MS/MS. Effervescent tablets, consisting of sodium bicarbonate, citric acid, and MHCPS in the case of honey and sodium bicarbonate and MHCPS in the case of milk, were used. The conditions for obtaining tablets were selected (the amount and ratio of the acid, base, and MHCPS in the composition of a tablet and its mass), ensuring the quantitative release of amphenicols. Procedures for the determination of amphenicols in honey and milk with the dispersion of the sorbent by carbon dioxide and the subsequent determination of the compounds by HPLC–MS/MS are developed. The limits of detection are 0.3–1 and 0.02–0.05 μg/kg for honey and milk, respectively.