摘要
建立液质联用法检测含乳果冻、布丁中三聚氰胺的方法。样品由于存在胶基,不能直接进行提取,在试验操作中应先对样品中胶基溶解,通过1%三氯乙酸-乙腈溶液提取,经过阳离子交换固相萃取柱进行净化,液相色谱-质谱/质谱法(LC-MS/MS)进行测定,比较外标法和内标法消除液质联用中基质效应带来影响,并进行方法学验证。结果表明,外标法和内标法精密度可靠,但是外标法加标回收较低,内标法平均加标回收率较好。内标法方法学验证结果表明:在质量浓度为5~100 ng/mL呈线性相关,r=0.9995;在加标质量分数为10,25和50μg/kg水平下,加标回收率分别为布丁99.9%~103.9%、果冻101.7%~105.7%;方法精密度分别为布丁0.4%~1.4%、果冻1.6%~2.6%。相比外标法,内标法虽然过程较繁杂,但能很好消除基质效应带来的影响,对样品三聚氰胺回收效果更好,加标回收率更高。
Establish a LC-MS/MS method for the detection of melamine in milk-containing jelly and pudding.The sample couldn’t be extracted directly because of the existence of gum base,so the gum base in the sample should be dissolved firstly in the test operation,and the melamine was extracted by 1%trichloroacetic acid-acetonitrile solution,purified by cation exchange solid phase extraction column,and determined by LC-MS/MS.The external standard method and internal standard method were compared to eliminate the influence of matrix effect in LC-MS/MS,and the methodology was verified.The results showed that the precision of external standard method and internal standard method were reliable,but the recovery rate of external standard method was low,and the average recovery rate of internal standard method was good.The results of methodological verification by internal standard method showed that there was a linear correlation in the concentration of 5-100 ng/mL,r=0.9995.At the spiked concentrations of 10,25 and 50μg/kg,the recoveries were 99.9%-103.9%for pudding and 101.7%-105.7%for jelly.The precision of the method was 0.4%-1.4%for pudding and 1.6%-2.6%for jelly.Compared with the external standard method,the internal standard method had a more complicated process,but it could well eliminate the influence brought by matrix effect,and had a better recovery effect on the sample melamine with a higher recovery rate.
作者
刘超
吕雪梅
景赞
LIU Chao;LÜXuemei;JING Zan(Leshan Institute for Food and Drug Control,Leshan 614000)
出处
《食品工业》
CAS
2023年第7期309-313,共5页
The Food Industry
基金
乐山市科技局重点研究项目(编号:22SZD007)。
