摘要
由于受到铌、锆的质谱干扰,使用电感耦合等离子体质谱法(ICP-MS)很难准确测定土壤和水系沉积物中的银。本文采用电感耦合等离子体串联质谱法(ICP-MS/MS),通过研究^(93)Nb^(16)O^(+)、^(91)Zr^(16)OH^(+)2、^(92)Zr^(16)OH^(+)和^(109)Ag^(+)在氦气、氧气和氨气中质谱信号变化,探讨不同碰撞/反应模式的干扰消除能力和消除机理。实验采用盐酸-硝酸-氢氟酸-高氯酸消解样品,选用氦气MS/MS模式、氧气MS/MS模式、氨气MS/MS模式、氨气Mass-Shift模式测定土壤和水系沉积物中的银含量。结果表明:在优化池气体流速后,四种模式下铌、锆对银的干扰程度分别降低20、1500、1500和2000多倍;方法检出限分别为0.005mg/kg、0.002mg/kg、0.003 mg/kg和0.003mg/kg;准确度和精密度采用国家标准物质验证,测定值和标准值的相对误差分别在-1.4%~84.3%、-7.6%~7.2%、-15.0%~10.0%和-12.5%~8.6%之间,相对标准偏差(RSD)分别在1.5%~6.3%、1.4%~8.3%、1.4%~5.9%和0.7%~8.2%之间。氦气MS/MS模式消除干扰能力一般,仅适合测定铌、锆干扰较轻的样品;氧气MS/MS模式、氨气MS/MS模式、氨气Mass-Shift模式消除质谱干扰能力较强,可用于土壤和水系沉积物中痕量银的测定。与行业标准DZ/T 0279.11—2016相比,这三种方法检出限更低、测定范围更宽,并可实现多元素同时测定。
BACKGROUND:It is difficult to accurately determine the content of Ag in soil and sediment due to the mass spectrum interference of niobium,zirconium oxide and hydroxide during inductively coupled plasma-mass spectrometry(ICP-MS)analysis.OBJECTIVES:To develop methods for the determination of trace Ag in soil and sediment samples by four collision/reaction modes.METHODS:The changes of mass spectrum signals of ^(93)Nb^(16)O^(+),^(91)Zr^(16)OH^(+)2,^(92)Zr^(16)OH^(+)and ^(109)Ag^(+)in helium,oxygen and ammonia were determined using inductively coupled plasma-tandem mass spectrometry(ICP-MS/MS).The interference elimination ability and elimination mechanism of different collision/reaction modes were investigated.The samples were digested by HCl-HNO3-HF-HClO4.The content of Ag in soil and stream sediments was determined by helium MS/MS mode,oxygen MS/MS mode,ammonia MS/MS mode and ammonia Mass-Shift mode.RESULTS:With the optimal gas flow rate in the tank of the four collision/reaction modes,the interference degree of niobium and zirconium on Ag were decreased more than 20,1500,1500 and 2000 times,respectively.The detection limits of the method were 0.005mg/kg,0.002mg/kg,0.003mg/kg and 0.003mg/kg,respectively.The accuracy and precision were verified by national reference materials of soil and sediment,while the relative errors of measured values and certified values were-1.4%-84.3%,-7.6%-7.2%,-15.0%-10.0%and-12.5%-8.6%,respectively.The relative standard deviations were 1.5%-6.3%,1.4%-8.3%,1.4%-5.9%and 0.7%-8.2%,respectively.CONCLUSIONS:Helium MS/MS mode has a low capacity to eliminate mass spectrometry interference,and is suitable for the determination of samples with little interference of niobium and zirconium.Oxygen MS/MS,ammonia MS/MS and ammonia Mass-Shift modes have a strong ability to eliminate mass spectrometry interference,which can be used for the determination of trace Ag in soil and stream sediments;and have the advantages of lower detection limit,wider linear range,and simultaneous determination of multiple
作者
刘跃
林冬
王记鲁
李静
王鑫
LIU Yue;LIN Dong;WANG Jilu;LI Jing;WANG Xin(Tianjin Eco-Environmental Monitoring Center,Tianjin 300191,China)
出处
《岩矿测试》
CAS
CSCD
北大核心
2022年第6期1017-1028,共12页
Rock and Mineral Analysis
基金
生态环境部标准编制项目[2018-4]。
关键词
碰撞/反应模式
银
电感耦合等离子体串联质谱法
土壤
水系沉积物
collision/reaction modes
silver
inductively coupled plasma-tandem mass spectrometry
soil
stream sediments
