固相萃取-液相色谱-串联质谱法测定鸡蛋中小檗碱残留量

Determination of berberine residues in eggs by solid phase extraction coupled with liquid chromatography-tandem mass spectrometry

目的建立固相萃取-液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定鸡蛋中小檗碱残留量的检测方法。方法样品经80%(V/V)乙腈溶液提取,经过混合阳离子(mixed-mode,strongcation-exchange,MCX)固相萃取柱净化。采用0.1%甲酸(V/V)-甲醇溶液(A)和0.1%甲酸-5 mmol/L乙酸铵溶液(B)进行梯度洗脱,采用正离子模式,多反应监测,基质匹配外标法定量分析。结果小檗碱进样浓度在2~100ng/mL范围内与峰面积呈良好的线性关系(r^2=0.999);方法检出限和定量限分别为0.5和1.0μg/kg;在1.0、2.0、10.0μg/kg3个添加水平下,回收率在62.2%~108.3%之间,相对标准偏差为5.6%~9.8%(n=6)。结论本方法简便、准确、快速、灵敏,适用于鸡蛋中小檗碱残留量的检测。

Objective To establish a method for determination of berberine in eggs by solid phase extraction coupled with liquid chromatography-tandem mass spectrometric(LC–MS/MS).Methods Eggs samples were extracted with 80%(V/V)acetonitrile solution and then the extracts were purified by the MCX(mixed-mode,strong cation-exchange)solid phase extraction.The gradient elution was carried out with 0.1%(V/V)formic acid methanol(A)and 0.1%formic acid-5 mmol/L ammonium acetate solution(B).Electrospray positive ion source(ESI+),multiple reaction monitoring(MRM)mode and the matrix-matching external standard method were applied for quantitative analysis.Results There was a good linear correlation between the peak areas and the concentrations of berberine at the range of 2.0–100 ng/mL(r^2=0.999),the limit of detection and limit of quantification was 0.5 and 1.0μg/kg.The recovery rates were 62.2%–108.3%and the relative standard deviations were 5.6%–9.8%at the addition levels of 1.0,2.0 and 10.0μg/kg(n=6).Conclusion This method is simple,accurate,fast and sensitive and is suitable for determination of berberine residues in eggs.