顺序注射-氢化物发生-原子荧光光谱法测定海产品中无机硒和有机硒

摘要

The sample (2.500 0 g)of seafoods was extracted with HCl(1+1)solution 25 mL for 18 h at temperature of 60 ℃.After filtration on defatted cotton,the filtrate was extracted with 5 mL of n-hexane.An aliquot of 4.00 mL of the water phase was taken and the content of inorganic selenium was determined by HG-AFS with sequential inj ection.Total selenium in the sample was determined in a separate sample by AFS with microwave assisted sample treatment.The difference of total selenium and the inorganic selenium represents the organic selenium.Linear relationship between values of fluorescence intensity and mass concentration of inorganic selenium was kept in the range of 1.00-20.0μg·L-1 ,with detection limit (3s)of 0.113μg·L-1 .Tests for recovery and precision were made by standard addition method at the concentration levels of 0.100,1.00,2.00 mg·kg-1 , giving values of recovery and RSD′s (n= 6)in the ranges of 84.8%-93.5%and 1.6%-2.5%respectively.%海产品样品（2．5000 g）采用盐酸（1＋1）溶液25 mL于60℃提取18 h，经脱脂棉过滤，滤液经环己烷5 mL萃取后分层；取水相4．00 mL采用顺序注射-氢化物发生-原子荧光光谱法测定其中无机硒的含量。另取样按微波消解-原子荧光光谱法测定此样品中的总硒量。采用差减法计算有机硒的含量。无机硒的质量浓度在1．00～20．0μg·L－1范围内与其荧光强度呈线性关系，检出限（3s）为0．113μg·L－1。在0．100，1．00，2．00 mg·kg－1等3个浓度水平进行加标回收试验和精密度试验，回收率在84．8％～93．5％之间，测定值的相对标准偏差（n＝6）在1．6％～2．5％之间。