Abstract: An analytical method was established for the determination of the residues of 11 sulfonamides and five quinolones in infant formula milk powder using ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-MS/MS). Acidified acetonitrile was used for sample extraction and the extract was purified and concentrated by solid phase extraction (SPE) using a PRiME hydrophilic lipophilic balance (HLB) column, then separated on an XBridge BEH C18 column, detected in the positive ion mode using an electrospray ionization source, and quantified by the calibration curve method with matrix matching. The calibration curves of all analytes showed a good linear relationship in the concentration range of 2–100 ng/mL with correlation coefficients greater than 0.995 0. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.1-0.2 and 0.3-0.5 μg/kg, respectively. Recoveries for spiked samples were between 84.8% and 108.0%, with relative standard deviations (RSDs) between 0.36% and 5.41%. The proposed method is simple, efficient, reliable and sensitive.

Key words: infant formula milk powder; sulfonamides; quinolones; ultra-performance liquid chromatography tandem mass spectrometry; PRiME HLB solid phase extraction column

摘要： 基于超高效液相色谱串联三重四极杆质谱技术建立婴幼儿配方乳粉中11 种磺胺类和5 种喹诺酮类兽药残留的检测分析方法。样品提取剂为酸化乙腈，使用PRiME HLB固相萃取柱对提取液进行净化浓缩，经过XBridge BEH C18色谱柱分离后，采用电喷雾离子源，在正离子模式下选择多反应监测模式进行分析，用基质匹配标准曲线定量。结果表明：16 种兽药残留含量在质量浓度2～100 ng/mL具有良好的线性关系，线性相关系数（R2）大于0.995 0；检出限为0.1～0.2 μg/kg，定量限为0.3～0.5 μg/kg；样品加标回收率为84.8%～108.0%，相对标准偏差为0.36%～5.41%。本研究建立的检测婴幼儿配方乳粉中磺胺类等兽药残留的方法简便高效、稳定可靠，具有较高的灵敏度。

关键词: 婴幼儿配方乳粉；磺胺；喹诺酮；超高效液相色谱串联三重四极杆质谱法；PRiME HLB固相萃取柱