Switchable Hydrophilicity Dispersive Solvent-Based Liquid-Liquid Microextraction Coupling to High-Performance Liquid Chromatography for the Determination of Amphenicols in Food Products

Antibiotic residue has become a serious issue of food safety, due to the emergence of drug-resistant bacteria and their toxic side effects. Therefore, regarding the need, we herein report a rapid, sensitive, and selective switchable hydrophilicity dispersive solvent-based liquid-liquid microextraction (SHDS-LLME) method combined with high-performance liquid chromatography and UV detector for determining amphenicols in food products. In the off-line extraction procedure, the mixture of extraction solvent (butanol) and dispersive solvent (tetraethylenepentamine) was manually injected into the acidic aqueous sample solution. Specifically, after the fast neutralization reaction, the dispersive solvent was converted into water-soluble salt and phase separation was achieved. Under the optimal conditions, a good linearity was observed in the range of 0.27–50.0 μg kg−1. The limit of detection for chloramphenicol (CAP) and thiamphenicol (TAP) were 0.03 and 0.08 μg kg−1, respectively. Recoveries for the spiked samples obtained were between 81.5 and 113.5% and the relative standard deviation was less than 8.6%. The proposed method was successfully applied for the analysis of amphenicols in four food products.