679412-80-7Relevant academic research and scientific papers
Solid phase extraction and spectrophotometric determination of silver using 2-(2-quinolinylazo)-5-dimethylaminoaniline
Hu, Qiufen,Yang, Guangyu,Huang, Zhangjie,Yin, Jiayuan
, p. 108 - 110 (2007/10/03)
A new method for the determination of silver based on the rapid reaction of silver(I) with 2-(2-quinolinylazo)-5-dimethylaminoaniline (QADMAA) and the solid phase extraction of the coloured chelate was developed. The QADMAA reacts with silver to form a violet chelate with molar ratio 1:2 (silver to QADMAA) in the buffer solution of pH=6.5 and SDS medium. This chelate is enriched by solid phase extraction with C18 cartridge and a high enrichment factor is achieved. The molar absorptivity of the complex is 1.25×105 L mol-1 cm-1 at 585 nm, and Beer's law is obeyed in the range of 0.01-0.6 μg ml-1. This method is applied for the determination of silver in natural water with good results.
The synthesis of QADMAA and its application to the solid phase extraction and spectrophotometric determination of cobalt
Zhang, Yunhuai,Li, Zhong,Zhang, Shengtao,Yang, Guangyu,Yin, Jiayuang
, p. 28 - 32 (2007/10/03)
In this paper, the synthesis of a new chromogenic reagent, 2-(2-quinolylazo)-5-dimethylaminoaniline (QADMAA), is reported. A sensitive, selective and rapid method for the determination of cobalt based on the rapid reaction of cobalt(II) with QADMAA and the solid phase extraction of the Co(II)-QADMAA chelate with C18 membrane disks was developed. In the presence of a pH = 5.5 buffer solution and a cetyl trimethylammonium bromide (CTMAB) medium, QADMAA reacts with cobalt to form a violet complex with a molar ratio of 1:2 (cobalt to QADMAA). This chelate was enriched by solid phase extraction with C18 membrane disks and an enrichment factor of 50 was obtained. The molar absorptivity of the chelate is 1.32 × 105 L mol-1 cm-1 at 616 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 μg mL-1. The relative standard deviation for eleven replicate sample at the 0.01 μg mL-1 level is 1.35%. The detection limit reached 0.02 μg L-1 in the original samples. This method was applied with good results to the determination of cobalt in environmental samples.
