将实验室自制的高灵敏度原子荧光光谱系统与色谱分离、在线紫外光前处理装置联用，实现了元素形态的液相色谱分离、在线紫外消解、蒸气发生及原子荧光光谱测定，并以砷、硒两元素为例对系统的分析性能进行研究。样品通过加热混旋提取、离心、过滤，使用反相色谱柱并以5.0 mmol/L磷酸氢二铵缓冲溶液（pH 5.7）-0.5 mmol/L四丁基溴化铵（TBAB）-1％甲醇为流动相进行分离；三价砷（AsO3-3）、二甲基砷（ DMA）、一甲基砷（ MMA）、五价砷（ AsO3-4）可在7 min内进行分离和测定，硒代胱氨酸（ SeCys）、硒代蛋氨酸（ SeMet）、四价硒（ SeO2-3）、六价硒（ SeO2-4）的测定约需11 min。在优化实验条件下，方法检出限（ DLs，S/N=3）为0.08~0.74μg/L；相对标准偏差（ RSD，n=7）为1.4％~7.9％，实际样品的加标回收率为82.5％~116.5％；砷、硒各形态在0.28~40.0μg/L和0.38~80.0μg/L范围内线性良好。建立的联用系统稳定性好、检出限低，可实现样品中低浓度砷、硒形态的准确测定。%A self-mode labs high sensitive atomic fluorescence spectrometric detection system com-bined with liquid chromatography,online ultraviolet photochemical digesting and vapor generation de-vice was established and evaluated. Arsenic and selenium species in various samples were extracted by heating-shaking and centrifugal filtration. All the analytes were separated on a reversed-phase col-umn using mobile phase of 5. 0 mmol/L phosphate buffer(pH 5. 7)-0. 5 mmol/L tetrabutyl ammonium bromide(TBAB)-1% methanol. The separations of AsO3-3 ,DMA,MMA,AsO3-4 and SeCys,SeMet, SeO2-3 ,SeO2-4 were achieved within 7 min and 11 min,respectively. Under the optimized operating con-ditions,the detection limits(DLs,S/N=3)were in the range of 0. 08-0. 74 μg/L,and the relative standard deviations( RSD,n=7 )were 1. 4% -7. 9%. The standard spiked recoveries for real samples were in the range of 82. 5% -116. 5%. Linearities were obtained in the ranges of 0. 28-40. 0 μg/L for arsenic species and 0. 38-80. 0 μg/L for selenium species. The developed system was successfully ap-plied in the detection of low levels of arsenic and selenium species in matrices.
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