Extraction of Five Fluoroquinolones in Eggs by Magnetic Solid-Phase Extraction with Fe3O4-MoS2 and Determination by HPLC-UV

Based on the synthesis of Fe3O4-MoS2 as magnetic solid-phase extraction adsorbent, a convenient, rapid, and effective method for extracting five fluoroquinolones (FQs) (lomefloxacin, ciprofloxacin, ofloxacin, sparfloxacin, and enrofloxacin) from eggs and detecting their contents by high-performance liquid chromatography using an ultraviolet-visible detector was established. The synthesized adsorbent was characterized by x-ray diffraction spectroscopy, scanning electron microscopy, and vibrating sample magnetometry. This study optimized the parameters (adsorbent, time of adsorption and desorption, eluent, sample solution, pH, and others) affecting the analytical performance of this method. Following optimization, the method provided good linearity from 2.5 to 300 mu g L-1, correlation coefficients of determination from 0.9990 to 0.9997, limits of detection from 0.2 to 5.0 mu g L-1, and limits of quantification from 0.7 to 17 mu g L-1. The intra- and interday RSDs were less than 5%. The range of the spiked recoveries of FQs in eggs was 88.6 to 96.6%, and the RSDs were less than 5%.