摘要
建立氢化物发生–原子荧光光谱法测定高盐食品中微量铅的方法。试样经硝酸消解,以恒温加热–多重水洗赶酸,直至pH值不变。对实验条件进行优化,负高压为300 V,灯电流为80 mA,原子化高度为8 mm,还原剂为20 g/L硼氰化钾(含7 g/L氢氧化钠)。铅的质量浓度在0～25 ng/mL范围内与荧光强度呈良好的线性关系,线性相关系数r=0.998 5,方法检出限为0.009mg/kg。测定结果的相对标准偏差为0.43%～0.60%(n=11),加标回收率为90.5%～100.6%。食品含盐量在20%之内不影响铅的测定。用该法对高盐食品中的铅进行测定,测定结果与电感偶合等离子体质谱法测定结果相符。该方法扩展了应用范围,适用于基层检测检验机构对高盐食品中微量铅的检测。
The method for determining trace lead in high–salt foods by hydride–atomic fluorescence spectrometry was established.Nitric acid digestion and multiple water–washing method was used to remove the acid under the constant temperature heating,until the pH value unchanged.The experimental conditions were optimized as follows:the negative pressure was 300 V,lamp current was 80 mA,atomization height was 8 mm,reducing agent was 20 g/L potassium borohydride(containing 7 g/L sodium hydroxide).The mass concentration of lead was linear with fluorescence intensity in the range of 0–25 ng/mL,the correlation coefficient(r)was 0.998 5.The detection limit was 0.009 mg/kg.The relative standard deviation of the measurement results was 0.43%–0.60%(n=11).The standard recovery rate was 90.5%–100.6%.As the salt content of food was less than 20%,it did not affect the determination of lead.Lead in high–salt food was determined by this method,the results were consistent with those detected by inductively coupled plasma mass spectrometry.This method extends the application range of hydride atomic fluorescence method for the determination of trace lead in high–salt food,which is suitable for the detection of trace lead in high–salt food for basic inspection institutions.
作者
仲婧宇
王静爽
孙浩然
李继民
ZHONG Jingyu;WANG Jingshuang;SUN Haoran;LI Jimin(Yingkou Product Quality Supervision and Inspection Institute,Yingkou 115000,China;Yingkou Xishi District Environmental Supervision Bureau,Yingkou 115003,China;Yingkou Zhanqian District Market Supervision Bureau,Yingkou 115000,China)
出处
《化学分析计量》
CAS
2018年第6期95-98,102,共5页
Chemical Analysis And Meterage
关键词
氢化物发生-原子荧光光谱法
高盐食品
铅
多重水洗赶酸
hydride atomic fluorescence spectrometry
high–salt food
lead
multiple water–washing method to remove the acid
作者简介
通讯作者,仲婧宇,研究员级高工,主要从事质量管理和检验工作,E-mail:xing0322@163.com
