Development of an Enhanced Quick, Easy, Cheap, Effective, Rugged, and Safe Method for Determination of Quinolone Drug Residues in Quail Eggs

ABSTRACT An enhanced quick, easy, cheap, effective, rugged, and safe (QuEChERS) purification method utilizing multi‐walled carbon nanotubes (MWCNTs) has been developed and coupled with liquid chromatography‐tandem mass spectrometry for the determination of eight quinolone drug residues in quail eggs. The sample was extracted using ethylenediamine tetraacetic acid‐McIlvaine buffer (pH = 4.0) and 2% formic acid in acetonitrile, followed by salting out with MgSO 4 , and purification with primary secondary amine (PSA), MWCNT, and Octadecylsilane (C18). The method demonstrated linear relationships for the target compounds within the range of 2–100 µg/L with correlation coefficients ( r ) exceeding 0.99. The limits of detection and quantification were determined to be 0.4 and 0.8 µg/kg, respectively. Validation through a three‐level spiking test (low, medium, and high) in quail eggs resulted in an average recovery rate ranging from 86.8% to 113.7%, with relative standard deviations between 2.6% and 10.2% ( n = 6). This method offers rapid operation, excellent purification efficiency, and high sensitivity, making it suitable for the qualitative and quantitative analysis of quinolone drug residues in eggs. Application of this method to a batch of 20 quail eggs revealed the presence of enrofloxacin and ciprofloxacin, suggesting a potential risk of non‐compliant quinolones use in quail egg production.