Solid Phase Extraction and Spectrophotometric Determination of Silver with 2-(2-Quinolylazo)-5-Dimethylaminophenol
Autor: | Zhangjie Huang, Jiayuan Yin, Guangyu Yang, Qiufen Hu |
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Rok vydání: | 2005 |
Předmět: | |
Zdroj: | Journal of Analytical Chemistry. 60:498-502 |
ISSN: | 1608-3199 1061-9348 |
Popis: | A new chromogenic reagent, 2-(2-quinolylazo)-5-Dimethylaminophenol (QADMAP) was synthesized, and a sensitive, selective, and rapid method was developed for the determination of the μg/L level of silver ions. The method is based on the rapid reaction of silver(I) with QADMAP and the solid phase extraction of the colored chelate using a C18 cartridge. The QADMAP reacts with Ag(I) in the presence of a citric acid-sodium hydroxide buffer solution (pH 5.0) and a sodium dodecyl sulfonate (SDS) medium to form a violet chelate of molar ratio 1 : 2 (silver to QADMAP). This chelate was enriched by solid phase extraction with C18 cartridge, and the retained chelate was eluted from the cartridge using ethanol (with 1% acetic acid). In the ethanol medium (with 1% acetic acid), the molar absorptivity of the chelate was 1.25 × 105 L mol−1 cm−1 at 584 nm. Beer’s law was obeyed in the range 0.01–0.6 μg/mL. The relative standard deviation for eleven replicate samples of 0.01 μg/mL was 1.86%. The detection limit is 0.02 μg/L in the original samples. The method was applied to the determination of μg/L levels of silver ions in water with good results. |
Databáze: | OpenAIRE |
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