磷酸铵沉淀-DRC-ICP-MS法测定菜籽油中的微量硫  

Determination of sulphur in rapeseed oil by DRC-ICP-MS with an ammonium phosphate precipitation method

作　　者：倪张林[1,2] 汤富彬[1,2] 屈明华[1,2] 沈丹玉 

机构地区：[1]中国林业科学研究院亚热带林业研究所 [2]国家林业局经济林产品质量检验检测中心(杭州),富阳311400

出　　处：《分析试验室》2014年第3期325-328,共4页Chinese Journal of Analysis Laboratory

基　　金：国家林业局公益性行业科研专项经费(201204414)资助

摘　　要：建立了磷酸铵沉淀一电感耦合等离子体质谱法测定菜籽油中微量s的检测方法。采用微波消解处理样品，选择^48SO＋作为观察信号，在动态反应池（DRC）内，O2作为反应气，与试样中的S元素生成。^48SO＋,消除^15N^17O^＋，^16O^16O^＋等物质带来的质谱干扰；针对四级杆无法去除的^48Ca＋干扰（丰度：0．187％），通过加入磷酸铵生成沉淀去除，优化了沉淀所需磷酸铵用量及pH大小。方法的检出限为0．4mg／kg，对精炼菜籽油和初榨菜籽油进行不同水平的添加，回收率为82．4％～112％，精密度为1．6％～3．9％（n=7）。方法可用于菜籽油中S元素的测定。A method for the analysis of sulfur （S） in rapeseed oil using inductively coupled plasma mass spectrometry with ammonium phosphate precipitation has been proposed. Rapeseed Oil sample was digested by microwave, then S was detected as4SSO by ICP-MS in DRC O2 gas mode to eliminate spectral interference such asl5 NlT o ＋ ,16 O160 ＋. The4a Ca＋ spectral interference which cannot be eliminated by O2 gas was removed by adding ammonium phosphate. The usage of ammonium phosphate and pH value was optimized. The detection limits （DL） of this method for determination of sulphur in rapeseed Oil was 0. 4 mg/kg. The recoveries of the analytes from spiked samples were in the range of 82. 4%- 112%. The RSDs were in the range of 1.6% - 3.9%（n=7）.

关 键 词：硫 ICP—MS 菜籽油 磷酸铵沉淀 

分 类 号：O657.6[理学—分析化学]