Fluoroquinolones extraction from meat samples based on deep eutectic solvent formation

A simple, highly available and cheap approach for effective pretreatment of meat samples, based on the formation of deep eutectic solvent (DES), was proposed for the first time. The procedure assumed dissolution of a hydrogen bond acceptor of DES (quaternary ammonium salt) in homogenized meat sample, followed by heating with a hydrogen bond donor of DES (medium-chain alcohol). Heating the mixture promoted DES formation and separation of analytes from the meat sample into the DES phase formed. The developed approach was proven to be highly effective for ofloxacin and fleroxacin separation from meat samples (chicken and beef). It was shown, that the developed procedure provided higher extraction efficiency of analytes (extraction recovery 98–100 %) in comparison with conventional extraction in pre-synthesized viscous DES, composed of tetrabutylammonium bromide and heptanol (extraction recovery 33–67 %). The developed approach was coupled with high-performance liquid chromatography with fluorometric detection for the determination of ofloxacin and fleroxacin in real and spiked meat samples. The limits of detection obtained from peaks 3 times the signal-to-noise ratio were 10 μg kg⁻¹ for ofloxacin and 15 μg kg⁻¹ for fleroxacin.