一种用于原子吸收光谱法测定汞的低消耗空气分段顺序注射蒸汽发生系统。

A low consumption air-segmented sequential injection vapor generation system for the determination of mercury by atomic absorption spectrometry.

作者信息

Ma H B, Fang Z L, Wu J F, Liu S S

机构信息

Research Center for Analytical Sciences, Box 332, Northeastern University, Shenyang, 110006, China.

出版信息

Talanta. 1999 Jun;49(1):125-33. doi: 10.1016/s0039-9140(98)00365-8.

DOI:10.1016/s0039-9140(98)00365-8

PMID:18967583

Abstract

A sequential injection system for the determination of mercury by vapor generation atomic absorption spectrometry (VGAAS) using tetrahydoborate reductant was developed, characterized by prevention of sample and reagent mixing in the holding coil using small air segments and initiation of the vapor generation in a flow-through gas-liquid separator. Extremely small volumes of reductant of 15-30 mul (0.2-1.0% NaBH(4)) and sample acidity as low as 0.05 mol l(-1) HCl were sufficient for achieving performance similar to flow injection (FI) VGAAS systems. A sample throughput of 90 h(-1) was achieved with 400 mul samples with a precision of 2.0% RSD at 10 mug l(-1)Hg, and a detection limit of 0.1 mug l(-1) (3sigma). Reagent consumption was reduced by a factor of 25 in comparison to the FI-VGAAS system. Good agreement with the certified value was obtained for the determination of mercury in seawater in a standard reference sample.

摘要

开发了一种顺序注射系统，用于通过使用四氢硼酸盐还原剂的蒸气发生原子吸收光谱法（VGAAS）测定汞，其特点是使用小空气段防止样品和试剂在保持线圈中混合，并在流通式气液分离器中引发蒸气发生。仅15 - 30微升（0.2 - 1.0% NaBH₄）的极少量还原剂和低至0.05 mol l⁻¹ HCl的样品酸度就足以实现与流动注射（FI）VGAAS系统相似的性能。使用400微升样品时，样品通量达到90 h⁻¹，在10微克 l⁻¹ Hg时精密度为2.0% RSD，检测限为0.1微克 l⁻¹（3σ）。与FI - VGAAS系统相比，试剂消耗减少了25倍。在标准参考样品中测定海水中的汞时，与认证值取得了良好的一致性。