微波消解-氢化物发生原子荧光光谱法测茶叶中铅

Determination of lead in tea leaf by Microwave digestion HG-AFS

目的:建立茶叶中铅含量的微波消解-氢化物发生原子荧光光谱法。方法:试样采用微波消解技术消解,研究了在盐酸介质下与硼氢化钾生成氢化物在电热原子化器中产生荧光光谱的行为,并对各种分析条件进行优化和探讨。结果:样品消解完全彻底,加铅标准10μg/L,回收率88%～107%,仪器检出限为0.29μg/L,方法检出限为0.15μg/g,线性范围为0μg/L～50μg/L,r>0.999,RSD为0.97%～3.6%。结论:本法简便、稳定、危害小、灵敏度高、检出限低,对仪器、人员均无过高要求,只需一台单道或双道原子荧光光度计即可。

Objective：To determine lead level in tea leaf by microwave digestion-Hydride generation atomic fluorescence spectrometry.Methods： The test samples were treated with microwave digestion.Then under hydrochloric acid medium,hydride was generated by reaction of digested samples and potassium borohydride to get atomic lead.Results： The samples were digested completely.The recovery of the method was 88%~107%,the detection limits of the instrument and the method were 0.29 μg/L and 0.15 μg/L respectively,the linear range was 0 μg/L^50 μg/L（r0.999）,and the RSD was 0.97%~3.6%.Conclusion： The method had the advantages of simpleness,stability,harmlessness,high sensitivity and low detection limit,without tall order for instruments and staff,only a single-channel or dual-channel atomic fluorescence spectrometer was available.