Narcise Cristine Ingrid S, Coo Lilibeth Dlc, Del Mundo Florian R
Institute of Chemistry, University of the Philippines-Diliman, 1101 Quezon City, Manila, Philippines.
Talanta. 2005 Dec 15;68(2):298-304. doi: 10.1016/j.talanta.2005.08.055. Epub 2005 Oct 5.
A flow injection-column preconcentration-hydride generation atomic absorption spectrophotometric (FI-column-HGAAS) method was developed for determining mug/l levels of As(III) and As(V) in water samples, with simultaneous preconcentration and speciation. The speciation scheme involved determining As(V) at neutral pH and As(III+V) at pH 12, with As(III) obtained by difference. The enrichment factor (EF) increased with increase in sample loading volume from 2.5 to 10ml, and for preconcentration using the chloride-form anion exchange column, EFs ranged from 5 to 48 for As(V) and 4 to 24 for As(III+V), with corresponding detection limits of 0.03-0.3 and 0.07-0.3mug/l. Linear concentration range (LCR) also varied with sample loading volume, and for a 5-ml sample was 0.3-5 and 0.2-8mug/l for As(V) and As(III+V), respectively. Sample throughput, which decreased with increase in sample volume, was 8-17 samples/h. For the hydroxide-form column, the EFS for 2.5-10ml samples were 3-23 for As(V) and 2-15 for As(III+V), with corresponding detection limits of 0.07-0.4 and 0.1-0.5mug/l. The LCR for a 5-ml sample was 0.3-10mug/l for As(V) and 0.2-20mug/l for As(III+V). Sample throughput was 10-20 samples/h. The developed method has been effectively applied to tap water and mineral water samples, with recoveries ranging from 90 to 102% for 5-ml samples passed through the two columns.
建立了一种流动注射-柱预富集-氢化物发生原子吸收光谱法（FI-柱-HGAAS），用于测定水样中微克/升水平的As(III)和As(V)，可同时进行预富集和形态分析。形态分析方案包括在中性pH下测定As(V)，在pH 12下测定As(III+V)，通过差值获得As(III)。富集因子（EF）随着进样体积从2.5增加到10ml而增大，对于使用氯型阴离子交换柱进行预富集，As(V)的EF范围为5至48，As(III+V)的EF范围为4至24，相应的检测限为0.03 - 0.3和0.07 - 0.3微克/升。线性浓度范围（LCR）也随进样体积而变化，对于5ml样品，As(V)和As(III+V)的LCR分别为0.3 - 5和0.2 - 8微克/升。样品通量随样品体积增加而降低，为8 - 17个样品/小时。对于氢氧根型柱，2.5 - 10ml样品的EFs，As(V)为3至23，As(III+V)为2至15，相应的检测限为0.07 - 0.4和0.1 - 0.5微克/升。5ml样品的LCR，As(V)为0.3 - 10微克/升，As(III+V)为0.2 - 20微克/升。样品通量为10 - 20个样品/小时。所建立的方法已有效地应用于自来水和矿泉水样品，对于通过两根柱子的5ml样品，回收率范围为90%至102%。
