调味品中罗丹明B的高效液相色谱-串联质谱法测定及不确定度评价

Determination of Rhodamine B in foods by high performance liquid chromatography-tandem mass spectrometry and its uncertainty evaluation

建立高效液相色谱-串联质谱测定调味品中非法添加罗丹明B的分析方法,评定测定结果的不确定度。样品用乙腈提取后,经MCX固相萃取柱净化,Acclaim C18色谱柱分离,以甲醇和0.05%甲酸水溶液为流动相;串联质谱,电喷雾正离子（ESI＋）模式电离,多反应监测（MRM）模式分析测定。结果表明：罗丹明B在1.0~40.0μg/kg范围内呈现良好的线性关系,相关系数R2=0.999 6,检出限为0.2μg/kg,加标回收率为67.40%~125.20%,相对标准偏差（RSD）≤4.950%。另外,从标准品溶液配制、标准曲线拟合、样品称量、仪器、样品溶液测定重复性等方面,评定了测定结果的不确定度。该方法具有操作简单、灵敏度高、分析时间短、结果准确等优点,适合于大批样品中罗丹明B含量的测定。

An analytical method was developed for determinating the concentration of Rhodamine B by high performance liquid chromatography-tandem mass spectrometry and its uncertainty evaluation in foods.The samples were extracted with the acetonitrile,purified by MCX solid phase extraction column,then separated on a Acclaim C18 column with methanol-0. 05% formic acid solution as mobile phase,and detected by mass spectrometry using electrospray ionization（ ESI＋） in positive mode on multiple reaction monitoring（ MRM） scan mode.Results showed that the linear range of the method was 1. 0-40. 0 μg / kg with correlation coefficients greater than 0. 999 6. The limit of detection（ LOD） was 0. 2 μg / kg. The recoveries ranged from 67. 40% to 125. 20% and the relative standard deviations（ RSD） were not more than 4. 950%. In addition,items constituting measurement uncertainty involved preparation of standard solution,fitting of standard curve,weighing of samples,equipment and measurement repeatability of the sample solution were evaluated. Result showed that the proposed method was simple,highly sensitive,rapid,accurate,thus it is suitable for the determination of the Rhodamine B in foods.