[Objective] As a nutritious daily food,the safety and quality of milk is highly concerned.Quinolone drugs are widely used in the prevention and treatment of diseases in dairy cows due to their broad-spectrum antibacterial properties and low cost.However,irrational use may lead to its residues in milk,which poses potential threats to human health.The existing detection methods have problems such as complicated sample processing steps,limited detection items,and multiple detection interferences,which cannot meet the needs of efficient and accurate detection of multiple quinolone drugs in milk.Therefore,a high performance liquid chromatography-tandem mass spectrometry method was established to simultaneously detect the residues of 17 quinolone drugs,providing strong technical support for ensuring the safety and quality of milk.[Method] Quinolone drugs in the sample were extracted with acetonitrile and phosphate buffer,purified by HLB solid phase extraction column,eluted with 5% ammoniated methanol,separated by C18 chromatographic column with methanol-formic acid aqueous solution as the mobile phase. The mass spectrometry using electrospray positive ion mode（ESI+） and multiple reaction monitoring（MRM）. Detection was carried out using UPLC-MS（Waters UPLC-TQD）,and quantification was performed using the external standard method to enhance repeatability.[Result] All 17 quinolone drugs elminated within 6 minutes with good peak shapes,and the detection limit range of the method was 0.005~0.228 μg/kg,the quantitation limit range was 0.017~0.759 μg/kg,the recovery rate of the sample spiked was 60.0%~118.0%,and the RSD was 1.4%~19.9%. It meets the requirements of 4.1.5 and 4.1.6 in the“GB 5009.295—2023 National Food Safety Standard - General Rules for Validation of Chemical Analysis Methods”.[Conclusion] This method is easy to operate,has good stablility and high accuracy.It is suitable for the detection of 17 quinolone drugs residues in milk.

High performance liquid chromatography-mass spectrometry  /  quinolone  /  analysis method