高效液相色谱-串联质谱-PRIME HLB柱净化法测定牛乳中6种喹诺酮残留量OA

An analytical method based on purification using a PRIME HLB column coupled with high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was established for the simultaneous determination of six quinolone residues-ciprofloxacin,enrofloxacin,norfloxacin,sarafloxacin,ofloxacin,and pefloxacin-in bovine milk.The proposed procedure innovatively employs 0.1 mol/L ethylenediaminetetraacetic acid-Mcllvaine buffer combined with 1％formic acid-acetonitrile(2∶8,V/V)as the extraction system,followed by one-step purification using a PRIME HLB column.This approach markedly simplifies conventional solid-phase extraction and reduces the sample preparation time.The purified sample was concentrated by nitrogen blowing,reconstituted,and filtered through a membrane.The separation was achieved on a C18 column(3.0 mm × 100 mm,2.7 μm),and the HPLC-MS/MS system was operated in positive ion mode with multiple reaction monitoring.The results showed that the limits of detection for the six quinolones ranged from 0.04 to 0.10 μg/kg,and the limits of quantification from 0.13 to 0.33 μg/kg.Matrix-matched standard curves were adopted for quantification by the external standard method,which exhibited good linearity over the concentration range of 2-100 μg/L with a correlation coefficient ≥ 0.996 1.Average recoveries from milk samples spiked at concentration levels of 2-50 μg/kg ranged from 85.5％to 106.5％with relative standard deviations ranging from 1.60％to 4.75％(n=6).This method features rapid operation,accurate results,and high precision.It provides reliable technical support for the high-throughput screening of quinolone residues in large batches of bovine milk.