混酸体系-四级杆碰撞反应池-ICP/MS法测定含硅类食品添加剂中的铅和砷

Determination of Lead and Arsenic in Silicon-containing Food Additives by a Mixed Acid System-quadrupole Collision Reaction Cell-ICP/MS Method

该文建立了一种混酸体系-四级杆碰撞反应池-ICP/MS法(Inductively Coupled Plasma Mass Spectrometry,ICP/MS)测定含硅类食品添加剂中铅、砷的方法。样品用氢氟酸-盐酸-硝酸组成的混酸体系进行微波消解前处理,采用四级杆碰撞反应池-ICP/MS法进行铅、砷的同时测定,选取Pb208、As75作为测定目标元素,Bi209、Ge72做相应的内标元素,应用碰撞/反应池技术、氦气动能歧视(Kinetic Energy Discrimination,KED)模式进行分析检测。铅、砷在0.0005~0.1000μg/mL范围内线性关系良好,r2均大于0.999。对样品进行加标回收验证,铅、砷的回收率分别为92.0%~107.0%和94.0%~104.0%,相对标准偏差(Relative Standard Deviations,RSDs)分别为2.49%、1.68%,铅、砷的检出限分别为0.003和0.002 mg/kg。该方法具有高的准确度、灵敏度、精密度和很小的干扰性等优点,适合测定含硅类食品添加剂中的铅、砷,可用来进行含硅类食品添加剂的质量监控和安全评价。

A mixed acid system-quadrupole collision reaction cell-ICP/MS(Inductively Coupled Plasma Mass Spectrometry,ICP/MS)method for determination of lead and arsenic in silicion-containing food additives was set up.Samples were pretreated by microwave digestion with a mixed hydrofluoric acid-hydrochloric acid-nitric acid system,then the lead and arsenic were simultaneously determined by the quadruple collision cell-ICP/MS method,with Pb208 and As75 as the target elements for determination,Bi209 and Ge72 as the corresponding internal standard elements,and the collision/reaction cell technology and helium kinetic energy discrimination(KED)mode for analysis and detection.Lead and arsenic had a good linear relationship in the range of 0.0005~0.1000μg/mL with r2 greater than 0.999.The samples were subjected to standard addition recoveries experiments,and the spiked recoveries of lead and arsenic were 92.0%~107.0%and 94.0%~104.0%,respectively.The samples were spiked and recovered to verify that the recoveries of lead and arsenic were 2.49%and 1.68%,respectively.The detection limits of lead and arsenic were 0.003 mg/kg and 0.002 mg/kg,respectively.This method had advantages in terms of high accuracy,high sensitivity,high precision and little interference,which is suitable for the determination of lead and arsenic in silicon-containing food additives,as well as quality monitoring and safety evaluation of silicon-containing food additives.