超高效液相色谱-串联质谱法测定饲料中非法添加物二羟丙茶碱

Determination of illegal additive diprophylline in feed by ultra performance liquid chromatography-tandem mass spectrometry

目的建立超高效液相色谱-串联质谱法测定饲料中非法添加物二羟丙茶碱的分析方法。方法样品经0.2%甲酸水溶液提取,过混合型阳离子固相萃取柱(mixed cation solid phase extraction, MCX)净化,基质匹配标准溶液,外标法定量。采用甲醇(A)和0.2%甲酸水溶液(含5 mmol/L乙酸铵)(B)作为流动相进行梯度洗脱,质谱采用多反应检测模式(multiple reactions monitoring, MRM)对二羟丙茶碱的定量离子和定性离子进行监测。结果本方法在6.5min内完成目标化合物的分离分析。二羟丙茶碱在低中高不同浓度添加水平的回收率为80.0%~102%,相对标准偏差小于9%(n=5),方法定量限为0.05 mg/kg。结论该方法快速、准确、灵敏,适合测定饲料产品中非法添加物二羟丙茶碱药物残留。

Objective To establish a method for determining the illegal additive diprophylline in feed by ultra performance liquid chromatography-tandem mass spectrometry.Methods The samples were extracted with 0.2%formic acid aqueous solution,purified by a mixed cation solid phase extraction column,and quantified by external standard method after the matrix was matched with the standard solution.Gradient elution was performed using methanol(A)and 0.2%formic acid aqueous solution(containing 5 mmol/L ammonium acetate)(B)as the mobile phases,and the quantitative and qualitative ions of diprophylline were monitored by multiple reactions monitoring on the mass spectrum.Results The method completed the separation and analysis of the target compound in 6.5 min.The recoveries of diprophylline were 80.0%‒102%at low,medium and high levels with relative standard deviation less than 9%(n=5)and the limit of quantitation of 0.05 mg/kg.Conclusion The proposed method is fast,accurate and sensitive,which is suitable for detecting diprophylline residues in feed samples.