微波消解-电感耦合等离子体质谱法测定整蛋白型肠内营养剂中铁、锌、铜、锰元素含量

Content Determination of Fe,Zn,Cu and Mn in Intacted Protein Enteral Nutrition Powder by MAE-ICP-MS

目的建立测定整蛋白型肠内营养剂中铁(Fe)、锌(Zn)、铜(Cu)、锰(Mn)元素含量的微波消解-电感耦合等离子体质谱(MAEICP-MS)法。方法采用微波-硝酸消解处理整蛋白型肠内营养剂样品,采用ICP-MS法测定,射频功率为1350 W,载气流速为1.10 L/min,辅助气流速为1.20 L/min,氦气流速为4 L/min,加入锗元素(Ge)作为内标,校正由于样品基体效应和仪器信号漂移对测量产生的干扰。结果国家标准物质对比试验证明测定方法准确、可靠;各元素质量浓度在1~100μg/L范围内与峰面积线性关系良好,相关系数(r)≥0.9997,4种元素检出限范围为0.0426~0.1393μg/kg,回收率为100.41%~115.14%,精密度试验结果的RSD为0.78%~4.04%。结论该方法简便、灵敏、准确,可同时检测整蛋白型肠内营养剂中Fe,Zn,Cu,Mn 4种金属元素的含量。

Objective To determine the Fe,Zn,Cu and Mn in Intacted Protein Enteral Nutrition Powder by microwave digestion and inductively coupled plasma mass spectrometry(MAE-ICP-MS).Methods The Intacted Protein Enteral Nutrition Powder was digested by microwave and nitric acid and determined by ICP-MS.The RF power was 1350 W,the flow rate was 1.10 L/min for carrier gas,1.20 L/min for auxiliary gas,4 L/min for helium gas.The internal standard solution Ge was used to correct the interference caused by matrix effect and instrument signal drift.Results The national standard material comparison experiment demonstrated the validated method was accurate and reliable.The linear range of each element was in the range of 1-100μg/L,the correlation coefficient(r)≥0.9997.The detection limits of 4 elements were in the range of 0.0426-0.1393μg/kg.The recoveries were in the range of100.41%-115.14%,and the RSD of precision test was in the range of 0.78%-4.04%.Conclusion The method is simple,sensitive and accurate,which can be used for the simultaneous determination of Fe,Zn,Cu and Mn in Intacted Protein Enteral Nutrition Powder.