土豆中微量元素的质谱分析

Determination of trace elements in potato by inductively coupled plasma mass spectrometry

对土豆样品采用HNO3+H2O2混合酸消解体系进行微波消解处理制样,用电感耦合等离子体质谱(ICP-MS)法同时测定土豆中Na、Mg、Al、P、K、Ca、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Se、Pb共16种微量元素的含量。详细地研究了样品的前处理条件,选用Rh作内标元素校正基体效应和信号漂移,该方法对16种待测元素的检出限为0.005～0.236μg/L,通过添加标准进行加标回收,所有待测元素的回收率在92.20%～109.65%之间,相对标准偏差(RSD)均小于3.18%,结果准确可靠。该法可为土豆中微量元素的快速检测提供科学依据。

Samples of potato were digested by microwave digestion, and trace elements amounts of Na, Mg, AI, P, K,Ca,Cr, Mn, Fe, Co, Ni,Cu,Zn,As, Se and Pb in sample solutions were determined by inductively coupled plasma mass spectrometry（ICP-MS） .Sample preparation was achieved by digestion with HNO3 ＋ H202 in a closed-vessel microwave system.The pretreatment of sample was studied.Rh as internal standard element was used to compensate matrix effect and signal drift. Under the optimal conditions, the detection limits of the 16 elements were in the range of O.O05-0.236μg/L.The recovery was 92.20%-109.65% by adding standard recovery experiment,and the relative standard deviation （RSD）was less than 3.18% for all the elements.This method was simple,sensitive and precise,which could satisfy the sample examination request and provide scientific rationale for determining trace elements of potato.